Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

5‐N,N‐diarylaminothiazoles containing cyano and nitro groups were synthesized using the Pd‐catalyzed Buchwald‐Hartwig amination reaction with good yields. The cyano group in the resultant thiazole was reduced to a formyl group. This was then subjected to the Knoevenagel condensation reaction, leading to the formation of thiazoles with a dicyanovinyl group. The nitro group in the thiazole was reduced to an amino group, which was subsequently reacted with triphosgene, yielding a thiazole with an isocyanate group. These thiazoles, with their electron‐accepting properties, demonstrated absorption and emission spectra at longer wavelengths. Notably, the thiazole containing the dicyanovinyl group displayed a red emission. Tests for the detection of hydrazine, a hazardous volatile organic compound, were conducted using the synthesized thiazoles. The results showed that the dicyanovinyl group effectively responded to hydrazine hydrate, evidenced by changes in the absorption and emission spectra. This change in color was also visibly detectable to the naked eye.

DOI： 10.1002/ejoc.202301036

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Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/00958972.2023.2287970

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Language：English   Publishing type：Research paper (scientific journal)  

Invited for the cover of this issue is the group of Koh Sugamata, Mao Minoura, and co-workers at Rikkyo University. The image depicts triptycene-based metal-organic frameworks with honeycomb structures that collect carbon dioxide and hydrogen, in an analogy to bees collecting honey in their honeycombs. Read the full text of the article at 10.1002/chem.202302080.

DOI： 10.1002/chem.202303417

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Publisher：American Chemical Society (ACS)  

The synthesis, structure, and properties of a stable, linear 2-stannapropadiene are reported. The identical C=Sn bonds in this 2-stannapropadiene are the shortest hitherto reported C–Sn bonds. This 2-stannapropadiene features a 119Sn NMR signal at 507 ppm for the central tin atom, indicative of an unsaturated SnIV oxidation state. Treatment of this 2-stannapropadiene with SnCl2·dioxane resulted in the formation of a novel four-membered cyclic 1,1-dichloro-1,3-distannetane.

DOI： 10.26434/chemrxiv-2023-2d7rc

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Language：English   Publishing type：Research paper (scientific journal)  

A series of metal-organic frameworks (MOFs) based on zinc ions and two triptycene ligands of different size were synthesized under solvothermal conditions. The structural analyses revealed that these are isostructural three-dimensional-network MOFs. The high porosity and thermal stability of these MOFs can be attributed to the highly rigid triptycene-based ligands. Their BET specific surface areas depend on the size of the triptycene ligands. In contrast to these surface-area data, the H2 and CO2 adsorption of these MOFs is larger for MOFs with small pores. Consequently, we introduced functional groups to the bridge-head position of the triptycene ligands and investigated their effect on the gas-sorption properties. The corresponding results unveiled the role of the functional groups in the specific CO2 binding via an induced interaction between adsorbates and the functional groups. Excellent H2 and CO-2 properties in these MOFs were achieved in the absence of open metal sites.

DOI： 10.1002/chem.202302080

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Language：English   Publishing type：Research paper (scientific journal)  

The fundamental properties of azaporphyrins can be modulated over a wide range by changing the number of meso-nitrogen atoms. Reported herein are the first examples of 5,10,15,20-tetraaryl-5-azaporphyrinium (MTAMAP) salts, which were prepared via metal-templated cyclization of the corresponding zinc(II) and copper(II) complexes of 10-aryl-1-chloro-19-benzoyl-5,15-dimesityl-10-azabiladiene-ac. The inclusion of one meso-nitrogen atom in the 5,10,15,20-tetraarylporphyrin skeleton considerably changes the redox and optical properties as well as the degree of aromaticity of the porphyrin ring. The present findings suggest that MTAMAP salts would be promising scaffolds for the development of new azaporphyrin-based ionic fluorophores and photosensitizers.

DOI： 10.1002/chem.202302148

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The synthesis and isolation of the first examples of a tetraselenolane and a hexaselenepane, obtained from the reaction of a bissilylcarbenoid ((R2CBrLi)-C-Si; R-Si=SiMePh2) with elemental selenium, is reported. The molecular structures of these cyclic polyselenides were determined using single-crystal X-ray diffraction analysis. The selective synthesis of these polyselenides was achieved by controlling the reaction temperature. Stoichiometric deselenation of the hexaselenepane with triphenylphosphine afforded the corresponding tetraselenolane in quantitative yield. Further deselenation of the tetraselenolane with excess triphenylphosphine did not furnish the expected selenoketone but the diselenirane, as confirmed by spectroscopic analysis.

DOI： 10.1002/ejic.202200780

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Language：English   Publishing type：Research paper (scientific journal)  

Allenes (>C=C=C<) are classified as cumulated dienes with a linear structure and an sp-hybridized central carbon atom. We have synthesized and isolated a stable 2-germapropadiene with bulky silyl substituents. The 2-germapropadiene allene moiety adopts a linear structure both in the solid state and in solution. An X-ray diffraction electron-density-distribution (EDD) analysis of this 2-germapropadiene confirmed the linear C=Ge=C geometry with a formally sp-hybridized germanium atom that bears two orthogonal C=Ge π-bonds. Based on detailed structural and computational studies, we concluded that the linear geometry of the isolated 2-germapropadiene most likely arises from the negative hyperconjugation of the silyl substituents at the terminal carbon atoms. The 2-germapropadiene reacts rapidly with nucleophiles, indicating that the linearly oriented germanium atom is highly electrophilic.

DOI： 10.1002/anie.202302836

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Language：English   Publishing type：Research paper (scientific journal)  

We have developed highly porous Cu-based metal-organic frameworks (MOFs) using carbazole-type linkers. The novel topological structure of these MOFs was revealed by single-crystal X-ray diffraction analysis. Molecular adsorption/desorption experiments indicated that these MOFs are flexible and change their structure upon adsorption/desorption of organic solvents and gas molecules. These MOFs exhibit unprecedented properties that allow controlling their flexibility by adding a functional group onto the central benzene ring of the organic ligand. For example, the introduction of electron-donating substituents increases the robustness of the resulting MOFs. These MOFs also exhibit flexibility-dependent differences in gas-adsorption and -separation performance. Thus, this study represents the first example of controlling the flexibility of MOFs with the same topological structure via the substituent effect of functional groups introduced into the organic ligand.

DOI： 10.1002/chem.202203442

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Language：Japanese   Publisher：The Society of Synthetic Organic Chemistry, Japan  

Gas storage and separation are closely related to various aspects of human society, such as the alleviation of greenhouse effect, promoting clean energy, and controlling harmful gases. In particular, hydrogen has been enthusiastically researched as a clean energy source that emits no greenhouse gases. Therefore, there are requirements for safe methods to manufacture, store, and transport hydrogen. Conventionally, hydrogen storage materials are metal hydrides and metal amides that react violently with moisture, and their usage environments are limited by the extreme conditions required for hydrogen gas generation. Metal-organic frameworks (PCP/MOFs) are porous coordination materials that are composed of organic ligands and metal ions. Because of their ability to efficiently adsorb small molecules, PCP/MOFs have potential applications in e.g., gas adsorption, catalysis, as well as energy storage and conversion. Functionalization and modification of the organic ligands to construct new MOFs are fascinating and significant areas in crystal engineering owing to the potential applications of the resulting materials. We describe the synthesis and gas-adsorption properties of novel MOFs using the functionalized organic ligands.

DOI： 10.5059/yukigoseikyokaishi.81.46

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Publishing type：Research paper (scientific journal)   Publisher：Georg Thieme Verlag KG  

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The reaction of phosphonates carrying a binaphthyl group with a range of Grignard reagents was complete within two hours at 0 °C to give phosphinates carrying a hydroxybinaphthyl group with high ­efficiency and diastereoselectivity. The resulting phosphinates were further subjected to a substitution reaction with MeMgBr. The reaction at reflux temperature in THF or toluene permitted the formation of P-chirogenic tertiary phosphine oxides with a high enantiomeric ratio. Rare examples of P-chirogenic alkynyl phosphine oxides were also obtained. The sequential one-pot substitution reaction of phosphonates bearing a binaphthyl group with two different Grignard reagents successfully gave the corresponding P-chirogenic phosphine oxides with enantiomeric ratios nearly equal to those of oxides derived from two-step reactions.

DOI： 10.1055/a-1979-6245

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Language：English   Publishing type：Research paper (scientific journal)  

Compounds with multiple bonds between elements of the second and fifth periods are extremely unstable, and systematic investigations into their properties remain elusive. Herein, we report a tellurium-centered heteroallene that contains multiple bonds between carbon and tellurium. This compound is the first example of bis(methylene)-λ4-tellane, which was synthesized and fully characterized using multinuclear NMR spectroscopy and X-ray crystallography. In the solid state, this λ4-tellane exhibits a bent allene structure for the C═Te═C moiety and unsaturated Te-C bonds. Interestingly, the allene-type structure is retained in the solution, which is reflected in an absorption band due to the π-π* transition at 610 nm. This λ4-tellane also exhibits unique reactivity toward dihalogermylenes, which yielded rare cyclic telluragermetanes.

DOI： 10.1021/acs.inorgchem.2c02697

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Publishing type：Research paper (scientific journal)   Publisher：Georg Thieme Verlag KG  

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Two-step transesterification of four-coordinate pentavalent organophosphorus compounds with a binaphthyl group has been studied in detail. The first step involves transfer of the axial chirality of a ­hydroxybinaphthyl group to the central chirality of the phosphorus atom. The second step is the substitution reaction of P-chirogenic compounds with a hydroxybinaphthyl group with lithium alkoxides, leading to the formation of P-chirogenic phosphates and phosphonates with primary and secondary alkoxy groups.

DOI： 10.1055/a-1948-3003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society ({ACS})  

1,2,5,10-Tetraphenylanthra[2,3-b]phosphole oxides and 1-methyl-1,2,5,10-tetraphenylanthra[2,3-b]phospholium salts were prepared, and their optical properties were investigated. The substituent at the para position and the fused anthracene moiety were found to exert significant impacts on the fluorescence properties of the P-bridged 2-styrylanthracene skeleton.

DOI： 10.1021/acs.joc.2c01107

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Herein, we report a series of 9-(diphenylphosphoryl)-10-(phenylethynyl)anthracenes (DPPPEAs) as novel fluorescent 9,10-disubstituted anthracene derivatives. The DPPPEAs were prepared by Sonogashira coupling of (10-bromoanthracen-9-yl)diphenylphosphine oxide with terminal arylacetylenes, and their structures were fully characterized. UV/Vis fluorescence spectroscopy and theoretical calculations were used to evaluate substituent effects on fluorescence properties of DPPPEAs. The nature of emissive excited state of DPPPEAs was found to vary greatly depending on the substituent, solvent, and temperature. Unsubstituted DPPPEA emitted intense fluorescence from locally excited (LE) state, whereas donor-acceptor (D-A) type DPPPEAs substituted with diphenylamino groups showed strong solvatofluorochromism derived from the charge-transfer (CT) state. Notably, carbazolyl derivatives exhibited fluorescence from LE hybridized with CT state. The disappearance of CT emission in rigid media suggests that solvent reorganization plays a crucial role in producing large Stokes shifts of D-A type derivatives. The DPPPEAs have also been found to function as annihilators in porphyrin-sensitized triplet–triplet annihilation processes.

DOI： 10.1002/cptc.202200100

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

The substitution reaction of phosphinates with a binaphthyloxy group at the phosphorus atom with lithium alkoxides proceeded with good to high efficiencies to give P-chirogenic phosphinates with a high enantiomeric ratio. As alcohols, primary, secondary, and tertiary alcohols could be used, and the use of tert-butyl alcohol yielded the products with a higher enantiomeric ratio. A substrate with two different alkyl groups on the phosphorus atom could also participate in the substitution reaction to give the corresponding products in good yields with excellent selectivity. The molecular structures of one of the substrates and the corresponding products, determined by X-ray analyses, proved that the substitution reaction at the phosphorus atom proceeded with inversion of the absolute configuration. The usefulness of the reaction was demonstrated by using it to prepare a drug candidate for Duchenne muscular dystrophy. Finally, thionation of the resulting phosphinates was carried out to form P-chirogenic phosphinothioates.

DOI： 10.1002/open.202100294

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The synthesis, excited state dynamics, and substituent effect on the 1O2-generation efficiency of several copper(II) complexes of 5,15-diazaporphyrin (CuDAPs) bearing peripheral substituents are reported. 10,20-Diaryl-CuDAPs were prepared via a new method consisting of metal-templated cyclization and N-dealkylation as key steps. The effect of the β-substituents on the optical and redox properties of CuDAP was stronger than that of the meso-aryl groups, which can be explained by considering the characteristics of the HOMO and LUMO of the DAP ring. The excited state dynamics and 1O2-generation efficiency of CuDAPs were studied using time-resolved spectroscopic techniques; the electronic effect of the meso-aryl groups on the triplet lifetime and 1O2-generation quantum yield was relatively weak, whereas that of the β-(1-pyrazolyl) groups was appreciable. The analysis of the temperature dependence of phosphorescence spectra of 10,20-bis(2,4,6-trimethylphenyl)-CuDAP allowed the energy gap between the excited trip-quartet and trip-doublet states to be determined. The relatively long triplet lifetimes of CuDAPs show their potential for future application as photosensitizers.

DOI： 10.1246/bcsj.20220002

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DOI： 10.3390/org2040023

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

This work reports a series of covalently linked hybrids comprising 5,10,15,20-tetraaryl-5,15-diazaporphyrinoids (M-TADAP; M = Ni, Zn, Cu) and amines. M-TADAP-amine hybrids were prepared via the metal-templated cyclization of the corresponding metal(II)-dipyrrin complexes and redox reactions on the DAP unit. In the UV/vis/near-IR absorption spectra of the hybrids containing an 18π-electron DAP ring, broad charge-transfer bands were observed, reflecting the electron-donating property of the para-aminophenyl groups and the electron-accepting property of the 18π TADAP dication. The electrochemical behavior of the M-TADAP-amine hybrids was strongly dependent on the structure of the peripheral amine units. Further electrochemical oxidation of the hybrids bearing N-Ph groups conceivably generated amine-centered radicals, which sequentially underwent irreversible coupling to form benzidine-linked M-TADAP polymer films. The Ni-TADAP-benzidine polymer exhibited the electric conductivity of 2×10−3 S m−1.

DOI： 10.1002/cplu.202100429

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Zinc terephthalate metal−organic framework (MOF) MOF-5 and some of its dialkylated derivatives (R2-MOF-5; R=Me, Et, Pr, Bu) were obtained from a solvothermal synthesis using 2,5-dialkyl-1,4-benzenedicarboxylic acids with zinc nitrite. The effect of the solvent on the solvothermal synthesis of R2-MOF-5 was investigated. For R=H and Me, interpenetrating or non-interpenetrating MOFs obtained depending on the choice of reaction solvent, while for R=Et, Pr, and Bu, no such solvent effect was observed, and only jungle-gym-type MOFs were generated. All compounds were fully characterized using powder X-ray diffraction analysis (PXRD), Fourier-transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA). After activation, all these compounds exhibit significant porosity, as confirmed by N2-, H2-, and CO2-sorption experiments. The N2-adsorption capacity of these compounds depends on the size of the attached alkyl groups, while the H2-uptake values tend to increase for the alkyl-functionalized MOFs relative to the unfunctionalized parent MOFs and exhibit a maximum value for Pr2-MOF-5.

DOI： 10.1002/ejic.202100466

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Dialkyl-diphosphenes and -distibenes of the type RTrp*2E2 (E = P, Sb; R = H, n-Pr) were synthesized and isolated using the steric protection of extended triptycyl groups (Trp*). The solubility of these diphosphenes and distibenes can be increased by installing a propyl group onto the bridgehead position of the triptycyl core (n-PrTrp*).

DOI： 10.1246/bcsj.20210350

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry ({RSC})  

Novel metal-organic frameworks (MOFs) based on thiabendazole (TBZ) were developed. The two structurally distinct TBZ-MOFs synthesized in this study exhibited enhanced durability and a broader biocidal spectrum than either individual bioactive species (i.e., Zn2+ and TBZ). The characteristics of each TBZ-MOF are related to the coordination modes among the Zn2+ ions and ligand donors. The difference in water solubility between the two TBZ-MOFs due to the structural design allows for the controlled release of the desired bioactive component.

DOI： 10.1039/D1DT00733E

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

P-Stereogenic phosphonothioates have attracted great attention due to their potent biological activities as analogues of phosphoric acids and phosphorothioates. We demonstrate here straightforward access to P-stereogenic phosphonothioates through the use of binaphthyl phosphonothioates as a chiral template. The first-step alcoholysis of binaphthyl phosphonothioates proceeded via a transfer of the axial chirality of a binaphthyl group to the central chirality of a phosphorus atom to give only monoalcohol adducts with moderate to excellent diastereoselectivities. Further alcoholysis of the obtained products in the presence of a small excess of alcohol and base proceeded with complete elimination of a binaphthyl group to give the corresponding P-stereogenic phosphonothioates with high enantiomeric excess. A DFT study of the reaction mechanisms in first-step alcoholysis indicated that the coordination of a sulfur atom to a sodium cation is the key factor in controlling the diastereoselectivities. This method can be applied to prepare both stereoisomers of a G6P analogue with high diastereomeric purity.

DOI： 10.1021/acs.joc.0c00687

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Language：English   Publishing type：Research paper (scientific journal)  

The first example of an interpenetrated methyl-modified MOF-5 with the formula Zn4O(DMBDC)3(DMF)2, where DMBDC2- is 2,5-dimethylbenzene-1,4-dicarboxylate and DMF is N,N-dimethylformamide (henceforth denoted as Me2MOF-5-int), namely, poly[tris(μ4-2,5-dimethylbenzene-1,4-dicarboxylato)bis(N,N-dimethylformamide)-μ4-oxido-tetrazinc(II)], [Zn4(C10H8O4)3O(C3H7NO)2]n, has been obtained from a solvothermal synthesis of 2,5-dimethylbenzene-1,4-dicarboxylic acid and Zn(NO3)2·6H2O in DMF. A systematic study revealed that the choice of solvent is of critical importance for the synthesis of phase-pure Me2MOF-5-int, which was thoroughly characterized by single-crystal and powder X-ray diffraction (PXRD), as well as by gas-adsorption analyses. The Brunauer-Emmett-Teller surface area of Me2MOF-5-int (660 m2 g-1), determined by N2 adsorption, is much lower than that of nonpenetrated Me2MOF-5 (2420 m2 g-1). However, Me2MOF-5-int displays an H2 uptake capacity of 1.26 wt% at 77 K and 1.0 bar, which is comparable to that of non-interpenetrated Me2MOF-5 (1.51 wt%).

DOI： 10.1107/S2053229620010177

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry ({RSC})  

Two mixed-ligand metal-organic frameworks, [Zn2(BDHA)0.5(INA)3] (MOF-1: H2BDHA = benzene-1,4-dihydroxamic acid; HINA = isonicotinic acid) and [Co2(BDHA)0.5(INA)3(DMF)] (MOF-2), were solvothermally synthesized and fully characterized by single-crystal X-ray crystallography as well as N2, H2, and CO2 gas-sorption measurements. The results constitute the first detailed analysis of the bonding environment around the hydroxamates in such MOFs, which are simultaneously decorated with Lewis-basic sites from the hydroxamate moieties and metal sites predisposed for coordinative unsaturation. MOF-2 shows a desirably selective adsorption of CO2 relative to N2.

DOI： 10.1039/d0dt01105c

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Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

A range of N,N-diarylthiazol-5-amines having a 4-pyridyl group on a thiazole ring were developed, and their photophysical properties were elucidated. Their synthesis was achieved by applying our methods to the combination of N-arylmethyl secondary thioamides and N,N-diarylthioformamides. This enabled us to obtain amines with different types of aromatic groups on the nitrogen atom. Their absorption and emission spectra in solution were examined. The 4-pyridyl group gives higher polarity to the amines. The solid-state emissions of the amines were also evaluated. Several amines showed mechanofluorochromism (MFC). A 4-pyridyl group on a thiazole ring was a requisite for the expression of MFC properties. Although N-(5thiazolyl) N,N-di(2-naphthyl)amines did not exhibit MFC by grinding of the pristine powder, white-light emission was observed when the ground powder was fumed with acetone vapor.

DOI： 10.1246/bcsj.20200083

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry ({RSC})  

The dinuclear (thio)(silyl)carbene and (seleno)(silyl)carbene gold(i) complexes1and2were obtained from the reaction of two equivalents of AuCl(SMe2) with the stable bis(methylene)-λ4-chalcogenanes3and4, respectively. The reaction proceeds under elimination of the chlorosilane moiety of3and4. Complexes1and2were characterized by spectroscopic and X-ray diffraction (XRD) analyses. The13C NMR signals for the carbene centers of 1 (309 ppm) and 2 (345 ppm) are by more than 150 ppm downfield shifted relative to those for other known (NHC)AuCl complexes. These results indicate that (chalcogeno)(silyl)carbenes, like (amino)(silyl)carbenes, belong to the push-spectator family of carbenes.

DOI： 10.1039/d0dt00967a

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The dialkylgermylene Trp*2Ge: (Trp*: peripherally extended sterically demanding alkyl groups based on the triptycyl (Trp) framework), was obtained from the reaction of Trp*Li with GeCl2¢ dioxane. The structure of Trp*2Ge: was unequivocally determined by NMR and UV-vis spectroscopy, mass spectrometry, and a single-crystal X-ray diffraction analysis. Moreover, the reactivity of Trp*2Ge: was examined.

DOI： 10.1246/BCSJ.20190338

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry ({RSC})  

A Naphthalene diimide (NDI)-incorporated helical thienoacene was developed. The compound has high electron mobility (1.4 cm2 V-1 s-1) thanks to its two-dimensional π-π interaction assisted by the intermolecular C-HO hydrogen bonding of the NDI moieties. Moreover, its bow-shaped π-skeleton reduces molecular fluctuation and gives the compound a thermally stable solid phase, which enables us to fabricate thermally stable organic devices.

DOI： 10.1039/D0CC04634E

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

2-(2-Hydroxyphenyl)-5-aminothiazoles were prepared by two different methods to elucidate their photophysical properties. The first synthetic method involved the addition of thioamide dianions derived from secondary thioamides and nBuLi to thioforamides. Alternatively, Pd-catalyzed sequential addition of aromatic groups and diarylamines to commercially available thiazoles led to the precursors of the desired thiazoles. The molecular structures of the resulting thiazoles were determined by X-ray analyses. The thiazoles showed dual-emission in cyclohexane and in the solid state.

DOI： 10.1002/ajoc.201900194

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ajoc.201900194

Language：English   Publishing type：Research paper (scientific journal)  

Nickel(II) and copper(II) complexes of redox-switchable 20π, 19π, and 18π 5,15-dialkyl-10,20-diaryl-5,15-diazaporphyrins were prepared through a metal-templated cyclization method. Furthermore, the terminal silyloxy groups in the peripheral N-alkyl chains were transformed into hydroxy groups by deprotection. It is worth noting that redox reactions between the 19π and 18π systems bearing hydroxy groups caused a change in the water solubility of the diazaporphyrin chromophore.

DOI： 10.1002/ajoc.201900085

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Hypervalent tetraaryltellurium(IV) compounds of the type Ar4TeIV(1: Ar = C6H5; 2: Ar = p-H3CC6H4; 3: Ar = p-t-BuC6H4; 4: Ar = p-F3CC6H4) were prepared via a convenient one-pot reaction between the isolated corresponding ArLi reagent and TeCl4. X-ray crystallographic analyses of 14 revealed distorted pseudo-trigonal-bipyramidal (TBP) structures for Ar4Te and the TBP character was analyzed by the dihedral angle method.

DOI： 10.1246/bcsj.20180380

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Bis(methylene)-λ4-selane 1, which represents a new class of heteroallenes, was synthesized and isolated as a stable purple crystalline solid. X-ray crystallographic analysis revealed a bent allene-type structure with pseudo C2v symmetry and a bent CSeC moiety that contains a 3-center-4-electron π-bond. The NMR spectrum of 1 shows compelling evidence for a slow rotation of the SeC moieties at room temperature. The 77Se NMR spectrum of 1 contains one signal in the region characteristic for Se(iv) compounds.

DOI： 10.1039/c9cc04121d

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Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry ({RSC})  

The intrinsic dynamic and static natures of the E⋯E′ interactions at the 1,8-positions of 1-(MeE)-8-(MeE′)C10H6 [1a-1f (E ≠ E′) and 1g-1j (E = E′)] were elucidated with QTAIM-DFA, after structural determination of 1-(PhE)-8-(PhE′)C10H6 (3a-3f), where (E, E′: x) = (O, S: A), (O, Se: b), (O, Te: c), (S, Se: d), (S, Te: e), (Se, Te: f), (O, O: g), (S, S: h), (Se, Se: i) and (Te, Te: j) (χE ≥ χE′). While the AB structures are confirmed for 3a, 3b and 3d-3f, which consist of the np(E)⋯σ∗(E′-CPh) interactions, the structure was BB for 3c, where the E-CR/E′-CR (R = Ph) bond is perpendicular to the naphthyl plane in A and it is placed on the plane in B. While the AB structures are determined by the p(E)-π(Ph) conjugations, the BB structure is by the crystal packing effect. The BA structure with np(E′)⋯σ∗(E-CPh) was not detected. While the nature of a typical hydrogen bond with covalency was predicted for BB, AA and BA, with the CT-MC (molecular complex formation through charge transfer) nature for AB in 1e and 1f (R = Me for E-CR/E′-CR), the CT-MC nature was predicted for all conformers of 1j, for example. NBO analysis for 1a-1f revealed that the acceptor orbitals contribute much more than the donor orbitals and the order is σ∗(O-CMe: <0.5 kcal mol-1) ≪ σ∗(S-CMe: ≈5 kcal mol-1) ≪ σ∗(Se-CMe: ≈10 kcal mol-1) ≪ σ∗(Te-CMe: ≈16 kcal mol-1) for np(S), np(Se) and np(Te). The E(2) values proportionally correlate to Cii-1 for AB and/or BA of 1a-1j, if analyzed separately for σ∗(S-C), σ∗(Se-C) and σ∗(Te-C).

DOI： 10.1039/c9nj02198a

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Aromaticity has been a central concept in chemistry since the discovery of benzene in the 19th century and has impacted the science of delocalized π-electron systems. The aromaticity of conventional aromatic compounds usually originates from electron delocalization through a single ring that consists of π-symmetric orbitals. Although double aromaticity, i.e. aromaticity composed of two circularly delocalized orbitals, has been theoretically predicted for over 20 years, the double aromaticity of a bench-stable compound is not well explored by experiment. Here we report the synthesis and isolation of the dication of hexakis(phenylselenyl)benzene, as well as its double aromaticity based on structural, energetic, and magnetic criteria. In this dication, cyclic σ-symmetric and π-symmetric delocalized orbitals are formally occupied by ten and six electrons, respectively, and the aromaticity thus follows the 4n + 2 (n = 1, 2,…) electron Hückel rule, regardless of the σ-orbital or π-orbital symmetry.

DOI： 10.1038/s42004-018-0057-4

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The hydrolysis of phosphonothioates with a binaphthyl group afforded the first example of O-(2′-hydroxy)binaphthyl phosphonothioic acids in good to high yields and >95:5 diastereoselectivity. The reaction proceeds via an axis-to-center chirality-transfer reaction. The ability of these acids to act as chiral molecular auxiliaries was demonstrated by using them as optically active ligands for the asymmetric ethylation of benzaldehyde and as a chiral discriminating agent for chiral aliphatic amines.

DOI： 10.1021/acs.orglett.8b00147

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Publisher：Wiley  

DOI： 10.1002/ange.201800471

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Trp*, a novel triptycene (Trp)-based aliphatic steric protection group was synthesized, and its potential to offer kinetic stabilization by steric protection was evaluated in the context of synthesizing a sulfenic acid (RSOH), i.e., a highly reactive sulfur-containing species. The isolated sulfenic acid Trp*SOH is thermally very stable, which clearly demonstrates the steric protection provided by Trp*.

DOI： 10.1246/cl.171230

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A novel, peripherally extended sterically demanding primary alkyl group based on the triptycene (Trp) framework, Trp∗CH2, was designed and synthesized via a convenient one-pot reaction using the Friedel-Crafts alkylation of the corresponding TrpCH2 precursor. The introduction of the Trp∗CH2 groups onto a Si=Si double bond allowed isolating the first stable tetraalkyldisilene that contains primary alkyl groups.

DOI： 10.1246/bcsj.20170422

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A neutral heterobimetallic triple-decker stannole complex was prepared by the reaction of an anionic ruthenocene bearing a stannole dianionic ligand with [Rh(cod)Cl]2 (cod = 1,5-cyclooctadiene), and the resulting Ru-Rh complex exhibits an electronic property different from those of the corresponding Ru-Ru and Rh-Rh complexes. The Ru-Rh complex can be decomposed in ionic liquids to metal nanoparticles.

DOI： 10.1039/C8DT01455H

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A series of Group 2 metal bis(arenecarbochalcogenoato)(crown ether) complexes M(EE′CAr)2(L)(L′)x (M = Mg, Ca, Sr, Ba; Ar = aryl; E = S, Se; E′ = O, S; L = H2O or THF; L′ = 15-crown-5, 18-crown-6) were synthesized and their structures were revealed by X-ray analyses. The two carbothioato ligands in Mg, Ca and Sr 15-crown-5 complexes are located on the same side of the crown ether plane, while those in Mg, Ca, Sr, and Ba 18-crown-6 compounds are on both sides of the 18-crown-6 plane (trans relative to the plane). For the Ca 15-crown-5 complex, both carbothioato ligands are connected to the central Ca ion through an oxygen atom in a monodentate manner, and the two hydrogen atoms of the coordinated water molecule are intramolecularly hydrogen-bonded with thiocarbonyl sulfur atoms. One of the two carbothioate groups in the Ca 18-crown-6 complex is connected in a bidentate manner to the central metal, while the other is connected in a monodentate manner through an oxygen atom. The two thiocarboxylato ligands in the Sr 15-crown-5 congener are connected in a bidentate fashion to the same side of the crown ether plane. The Ca and Sr compounds are the first examples of alkali earth metal carbochalcogenoate complexes in which carbochalcogenolato ligands are connected in a monodentate manner through an oxygen atom. Both chalcogenoato ligands in Ba(SOCC6H4Me-4)2(18-crown-6) and Sr(SeOCC6H4Me-4)2(18-crown-6) are coordinated in a bidentate manner to the central metal ion.

DOI： 10.1039/c8dt01959b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Chemical Society of Japan  

The β-functionalization of 5, 15-diazaporphyrins (DAPs) with phosphoryl, phenoxy, sulfanyl, and sulfonyl groups was achieved by either cross-coupling or aromatic nucleophilic substitution reactions of β-bromo- and β, β′-dibromo-DAPs. The heteroatom-containing functional groups at the β- positions strongly affected the redox properties of the DAP π-systems.

DOI： 10.1246/bcsj.20180123

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Royal Society of Chemistry  

Various 7-substituted benzo[b]phosphole derivatives were prepared by PO-directed lithiation of 1,2,3-triphenylbenzo[b]phosphole P-oxide and subsequent iodination and cross-coupling reactions. The electron-donating groups introduced at the 7-position produced dramatic solvatofluorochromism owing to the strong charge-transfer character of the excited state of the entire π-system.

DOI： 10.1039/c8dt01503a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

We have established a convenient method for the base-promoted direct amination of β-unsubstituted 5,15-diazaporphyrins (DAPs) with secondary and primary amines to produce 3,7,13,17-tetraamino- and 3-amino-DAPs, respectively, regioselectively. The amino groups attached at the periphery cause significant red shifts of the absorption bands as a result of their perturbation of the HOMO and/or LUMO in the DAP π-system. The palladium complex of a 3,7,13,17-tetrakis(diphenylamino)-DAP generated singlet oxygen in high yield under irradiation with near-infrared light.

DOI： 10.1002/anie.201800471

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

In spite of significant advances in redox-active porphyrin-based materials and catalysts, little attention has been paid to 20 pi and 19 pi porphyrins because of their instability in air. Here we report the meso-modification of 5,10,15,20-tetraarylporphyrin with two nitrogen atoms, which led to redox-switchable 20 pi, 19 pi, and 18 pi 5,10,15,20-tetraaryl-5,15-diazaporphyrinoids (TADAPs). Three kinds of metal(II) complexes and free bases of TADAP were prepared by the metal-templated annulation of the corresponding metal-bis(dipyrrin) complexes. The inductive and resonance effects of the meso-nitrogen atoms on the aromatic, optical, electrochemical, and magnetic properties of the entire TADAP pi-systems were assessed by using various spectroscopic measurements and density functional theory calculations. The aromaticity and pi-pi* electronic transition energies of the TADAPs varied considerably, and were shown to be dependent on the oxidation states of the pi-systems. In contrast to the isoelectronic 5,10,15,20-tetraarylporphyrin derivatives, the 20 pi and 19 pi TADAPs were chemically stable under air. In particular, the 19 pi TADAP radical cations were extremely stable towards dioxygen, moisture, and silica gel. This reflected the low-lying singly occupied molecular orbitals of their pi-systems and the efficient delocalization of their unshared electron spin. The capability of MgTADAP to catalyze aerobic biaryl formation from aryl Grignard reagents was demonstrated, which presumably involved a 19 pi/20 pi redox cycle.

DOI： 10.1002/chem.201703664

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We succeeded in the alignment of π skeletons, resulting in the formation of anisotropic crystals. The combination of plumbacyclopentadienylidene, which has a divalent lead atom incorporated into the π skeleton, and 1,4-dioxane afforded a coordination polymer, where the π skeletons are completely aligned in the same direction. The resulting plumbylene chains are also aligned in the same direction in the solid state, and therefore the crystals are noncentrosymmetric, showing second-harmonic generation (SHG) properties. Using pyrazine instead of 1,4-dioxane afforded an adduct composed of three plumbole units and two pyrazine molecules, and the crystals are symmetric and exhibit no SHG properties. The solid-state structures and optical properties are highly dependent on the Lewis base utilized. The present findings spotlight the use of group 14 divalent species incorporated into a π skeleton as a novel, useful method for the creation of a π-aligned coordination polymer with NLO properties.

DOI： 10.1021/acs.organomet.7b00217

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

NH-bridged and pyrazine-fused metallodiazaporphyrin dimers have been prepared from nickel(II) and copper(II) complexes of 3-amino-5,15-diazaporphyrin by Pd-catalyzed C-N cross-coupling and oxidative dimerization reactions, respectively. The synergistic effects of the nitrogen bridges and meso-nitrogen atoms play major roles in enhancing the light-harvesting properties and delocalization of an electron spin over the entire pi-skeletons of the metallodiazaporphyrin dimers.

DOI： 10.1002/asia.201700204

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An anionic ruthenocene derived from a dilithioplumbole complex was prepared. In the complex, the plumbole ligand coordinates a ruthenium atom in an η5-fashion, similar to the cyclopentadienyl ligand in ferrocene. The ruthenocene that has the aromatic π-ligand with the heaviest group 14 element reacted with electrophiles to afford the plumbole complexes wherein the plumbole ligands show deviation from planarity, in contrast to the planar plumbole ring in the anionic ruthenocene. The bent angles of the plumbole ligands are dependent on the substituents on the lead atoms. Cyclic voltammetry measurements revealed that the plumbole complexes are oxidized more easily than the corresponding stannole complexes.

DOI： 10.1039/c6sc04843a

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

NH-bridged and pyrazine-fused metallodiazaporphyrin dimers have been prepared from nickel(II) and copper(II) complexes of 3-amino-5,15-diazaporphyrin by Pd-catalyzed C-N cross-coupling and oxidative dimerization reactions, respectively. The synergistic effects of the nitrogen bridges and meso-nitrogen atoms play major roles in enhancing the light-harvesting properties and delocalization of an electron spin over the entire π-skeletons of the metallodiazaporphyrin dimers.

DOI： 10.1002/asia.201700204

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

In spite of significant advances in redox-active porphyrin-based materials and catalysts, little attention has been paid to 20π and 19π porphyrins because of their instability in air. Here we report the meso-modification of 5,10,15,20-tetraarylporphyrin with two nitrogen atoms, which led to redox-switchable 20π, 19π, and 18π 5,10,15,20-tetraaryl-5,15-diazaporphyrinoids (TADAPs). Three kinds of metal(II) complexes and free bases of TADAP were prepared by the metal-templated annulation of the corresponding metal-bis(dipyrrin) complexes. The inductive and resonance effects of the meso-nitrogen atoms on the aromatic, optical, electrochemical, and magnetic properties of the entire TADAP π-systems were assessed by using various spectroscopic measurements and density functional theory calculations. The aromaticity and π-π* electronic transition energies of the TADAPs varied considerably, and were shown to be dependent on the oxidation states of the π-systems. In contrast to the isoelectronic 5,10,15,20-tetraarylporphyrin derivatives, the 20π and 19π TADAPs were chemically stable under air. In particular, the 19π TADAP radical cations were extremely stable towards dioxygen, moisture, and silica gel. This reflected the low-lying singly occupied molecular orbitals of their π-systems and the efficient delocalization of their unshared electron spin. The capability of MgTADAP to catalyze aerobic biaryl formation from aryl Grignard reagents was demonstrated, which presumably involved a 19π/20π redox cycle.

DOI： 10.1002/chem.201703664

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Pentacene has attracted much attention as an organic electric material, but it often suffers from its very low solubility. We now report self-assembled rectangular host 18+ that has two pairs of terpyridine-PtII moieties aligned parallel to each other and connected by diyne linkers. The host encapsulated unsubstituted pentacene (2) with a remarkably strong binding constant of Ka ≈ 107 M-1 and solubilized it in acetonitrile up to the millimolar level. For smaller acenes (i.e., naphthalene to tetracene), a planar arrangement of two molecules inside the cavity was achieved. These results made it possible to analyze the acenes in the solution phase and provided a way to align the guests by a solution-processing method as a possible application, and thus, they contribute to fundamental physical organic chemistry as well as organic electronics.

DOI： 10.1002/ejoc.201600058

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Wiley  

The first examples of air-stable 20π-electron 5,10,15,20-tetraaryl-5,15-diaza-5,15-dihydroporphyrins, their 18π-electron dications, and the 19π-electron radical cation were prepared through metal-templated annulation of nickel(II) bis(5-arylamino-3-chloro-8-mesityldipyrrin) complexes followed by oxidation. The neutral 20π-electron derivatives are antiaromatic and the cationic 18π-electron derivatives are aromatic in terms of the magnetic criterion of aromaticity. The meso N atoms in these diazaporphyrinoids give rise to characteristic redox and optical properties for the compounds that are not typical of isoelectronic 5,10,15,20-tetraarylporphyrins.

DOI： 10.1002/anie.201510734

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The first examples of air-stable 20-electron 5,10,15,20-tetraaryl-5,15-diaza-5,15-dihydroporphyrins, their 18-electron dications, and the 19-electron radical cation were prepared through metal-templated annulation of nickel(II) bis(5-arylamino-3-chloro-8-mesityldipyrrin) complexes followed by oxidation. The neutral 20-electron derivatives are antiaromatic and the cationic 18-electron derivatives are aromatic in terms of the magnetic criterion of aromaticity. The meso Natoms in these diazaporphyrinoids give rise to characteristic redox and optical properties for the compounds that are not typical of isoelectronic 5,10,15,20-tetraarylporphyrins.

DOI： 10.1002/anie.201510734

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

Substitution reactions between a phosphoroselenoyl chloride and Grignard reagents proceeded smoothly at the phosphorus atom to furnish phosphonoselenoic acid esters. The resulting mixture of diastereoisomers could be readily distinguished on the basis of P-31 NMR, and separated by recrystallization or column chromatography to afford diastereoisomerically enriched products. For one of these diastereoisomers, the absolute configuration was determined by carrying out a single-crystal X-ray diffraction analysis.

DOI： 10.1039/c6ra00318d

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Reduction of THF-stabilized plumbacyclopentadienylidene with lithium afforded dilithioplumbole. On the other hand, oxidation of the dilithioplumbole provided the starting plumbacyclopentadienylidene. This is the unprecedented example of a reversible interconversion between group 14 M(ii) and its dianionic species bearing organic substituents. This journal is

DOI： 10.1039/c4cc09856k

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2,6-Bis[(diisopropylamino)methyl]phenyllithium 1 reacted with trichloroborane etherate to afford dichloroarylborane 4. The treatment of 4 with Ag triflate provided bistriflate 5. The reaction of 4 with AgBF<inf>4</inf>, however, afforded an unexpected product, borenium salt 6.

DOI： 10.1002/hc.21211

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The title trans and cis isomers (trans-3 and cis-3) were successfully synthesized as stable compounds by taking advantage of the Martin ligand. The X-ray crystallographic analysis of trans-3 showed that it has a distorted pseudotrigonal bipyramidal structure, and that the two phenyl groups at the 3-and 4-positions are cis to each other. The thermolysis of trans-3 in the presence of excess dimethyl acetylenedicarboxylate (DMAD) gave a mixture of the corresponding aziridines (trans-7 and cis-7) and cycloadducts (11a and 11b) of the azomethine ylides formed by ring opening of the aziridines with DMAD. Heating of cis-7 and excess DMAD under the same conditions gave diastereomeric mixtures of both the aziridines and the cycloadducts, which means that the stereochemistry of the aziridine formation from the 1,2-selenazetidine cannot be determined in this system.

DOI： 10.1002/hc.21177

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Dilithiostannoles, which are aromatic tin-containing ring compounds, were proposed to have stannylene character, as judged from their NMR analysis. We herein report on the synthesis of silyl-substituted dilithiostannoles, which were characterized by NMR spectroscopy and X-ray diffraction analysis. The silyl-substituted derivatives also exhibit features characteristic of aromatic dilithiostannoles such as 7Li NMR signals at high-field area and no C-C bond alternation in the stannole rings. Theoretical calculations and the 119Sn NMR chemical shifts revealed that the stannylene character in the silyl-substituted dilithiostannoles is enhanced due to greater interaction between 5p (Sn) and LUMO (butadiene) in comparison to those in alkyl and aryl derivatives. The 119Sn Mössbauer spectra of dilithiostannoles were measured for the first time, indicating that each of the tin atoms in dilithiostannoles can be characterized as having Sn(II) character. © 2014 American Chemical Society.

DOI： 10.1021/om5003717

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Publishing type：Research paper (international conference proceedings)  

The first stable stannanetriol and germanetriol bearing sterically congested aryl groups were synthesized by hydrolysis of the corresponding trichloro-stannane and-germane.The stannanetriol is monomeric in solution as well as in the crystalline state, as evidenced by X-ray diffraction analysis and CP-MAS NMR spectroscopy.The stannanetriol reacted with silicone grease to afford a cagelike compound having three Sn-O-Si-O-Sn linkages in the molecule.All the group 14 triols can be converted to the corresponding trihalo compounds in good yields.© 2014 Published by NRC Research Press.

DOI： 10.1139/cjc-2013-0496

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Tetracoordinated and pentacoordinated 1,2-thiazetidines bearing the Martin ligand, trans-5 and trans-6, were synthesized as stable compounds. The X-ray crystallographic analyses showed that trans-5 and trans-6 have distorted pseudotrigonal bipyramidal (pseudo-TBP) and TBP structures, respectively, and that the two phenyl groups at the 3- and 4-positions of both compounds are cis to each other. Thermal isomerization of the aziridine cis-11, which is considered a thermolysis product of trans-6, occurred even at relatively low temperature (100°C) in solution and made it difficult to determine the stereochemistry of the aziridine formation from trans-6 in solution. Flash vacuum pyrolysis, which potentially prevents the isomerization of the product, was applied to trans-6 to give eventually the stereochemistry-retained aziridine cis-11. This result indicates a ligand coupling pathway in the aziridine formation process from trans-6.

DOI： 10.1246/bcsj.20140132

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Asymmetric synthesis of P-chiral phosphorothioic monofluoridic acid ammonium salts was achieved via axis-to-center chirality transfer reactions by using phosphorothioic acid O-esters with a binaphthyl group, and the absolute stereochemistry of the salts was determined by X-ray analyses and by comparison of their CD spectra.

DOI： 10.1039/c4cc05198j

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Plumbacyclopentadienylidenes, in which the lead atoms have divalent states and are coordinated by THF, pyridine and N-heterocyclic carbene, were synthesized and characterized. The THF-and pyridine-stabilized compounds can be regarded as rare examples of hypervalent 10-X-4 species. The equilibrium between the THF adduct and the free plumbacyclopentadienylidene was evidenced by spectroscopic analysis and theoretical calculations. The THF adduct in benzene converted into a plumbylene dimer, where one of the lead centers is coordinated by THF and the other lead atom is coordinated by a divalent lead atom, the dimer gradually decomposing into spiroplumbole. The THF adduct unexpectedly reacted with trifluoroborane and trichlorogallane to afford fluoroborole and chlorogallole, which are the first examples of non-annulated fluoroborole and gallole, respectively. Plumbacyclopentadienylidenes, in which the lead atoms have divalent states and are coordinated by THF, pyridine, and an N-heterocyclic carbene, were synthesized and characterized. The THF-stabilized compound can be regarded as a rare example of hypervalent 10-X-4 species, which converts into a plumbylene dimer and reacts with trifluoroborane and trichlorogallane to afford the corresponding fluoroborole and chlorogallole, respectively (see scheme; R=Me2tBuSi). © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/chem.201303672

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A method for the introduction of various substituents at the 4 and 8 positions of 2,10-di-tert-butyldipyrido[1,2-c;2′,1′-e]imidazolium salts, is described. The new imidazolium salts bearing substituents (R′ = Cl, SPh) at the 4 and 8 positions are synthesized in three-step procedures, and carbenes generated from the imidazolium salts can be used to give the corresponding rhodium complexes. The role of the 4,8-substituents can be either bystanders or coordinating ligands according to the nature of the metal moiety. © 2013 American Chemical Society.

DOI： 10.1021/ic402301u

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The treatment of the o-ethynylphenyl isothiocyanates with primary and secondary amines in 1,2-DCE, followed by the addition of I2 and then heating resulted in the regio- and stereoselective tandem addition- iodocyclization to give the (4E)-2-amino-4-(1-iodomethylidene)benzo[d][1,3] thiazine derivatives as the sole product in high yields via the 6-exo-dig mode cyclization. The 2-alkoxy-1,3-benzothiazines were similarly produced from the o-ethynylphenyl isothiocyanates and the corresponding sodium alkoxides. © 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2013.05.069

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The oxidation of the 1-unsubstituted isotellurochromenes and isoselenochromenes with m-CPBA resulted in a novel ring-opening reaction to give the o-formyl distyryl ditellurides and diselenides as the sole products in good yields, respectively. The o-benzoyl distyryl ditelluride and diselenide were also produced from the corresponding 1-phenylisochromenes. In contrast, the 1-benzyl and 1-n-butylisochromenes were oxidized to afford the (Z)-1-benzylideneisochromenes and (Z)-1-butylideneisochromenes under similar conditions; no distyryl compounds were obtained. The distyryl compounds were also obtained by the hydrolysis of the corresponding 2-benzochalcogenopyrylium salts, which were easily converted from the 2-benzoisochromenes by treatment with triphenylcarbenium tetrafluoroborate (Ph 3C+BF 4-). © 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2012.07.023

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Triphenylenogermole, triphenylenodigermole, and trigermasumanene were prepared by repetitive lithiation of triphenylene followed by introduction of germanium functionalities. This is the first example of a trigermasumanene. Tin congeners were also synthesized and investigated. X-ray diffraction analysis of trisilasumanene 6, which does not have any substituents on the carbon atoms of the benzene rings, is also demonstrated. The optical properties of trigermasumanene and its derivatives were investigated by UV/Vis and fluorescence spectroscopy. Theoretical calculations were carried out to understand the properties of the thus-obtained triphenylenometallole derivatives. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/ejoc.201201223

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Undergoing a radical change! The reduction of dibenzo[a,e]pentalene by KC 8 afforded the corresponding anion radical, the structure of which was characterized for the first time by X-ray diffraction analysis. The electronic state of the anion radical is discussed with the aid of theoretical calculations. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/asia.201100711

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The reaction of pyridine-2,6-dicarboxylic acid (dipicolinic acid, dipicH2) with potassium tetraperoxochromate( V) in the mixture of water and ethanol led to the formation of a 2D s-d mixed-metal coordination polymer of {K[Cr(dipic)2]}n (1). The compound was characterized by spectroscopic methods (IR, Raman, UV/Vis). Single crystal X-ray diffraction analysis revealed that dipicolinate ligand is coordinated to the chromium(III) ion in an O,N,O0-tridentate fashion, while its uncoordinated and coordinated carboxylate O atoms (with respect to Cr(III) ion) are in turn bound to potassium ions. Therefore, each dipicolinate ligand bridges two potassium ions and a chromium(III) ion between them, giving rise to a 2D coordination network. The coordination of chromium(III) ions is octahedral, while the coordination number of potassium ions is 8. The coordination networks are in turn assembled only by π-π stacking interactions into a 3D structure. © The Author(s) 2011.

DOI： 10.1007/s10870-011-0242-0

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The ligand, 2-(2-(pyridin-2-yl)oxazolidin-3-yl)-N-(pyridin-2-ylmethylene) ethanamine, POPME, was prepared via microwave-supported Schiff base and oxazolidination reactions. The cadmium iodide complex [Cd2(POPME) (μ-I)2I2] was prepared and identified by elemental analysis, IR, Raman and 1H and 13C NMR spectroscopy and single-crystal X-ray diffraction. In the crystal structure two Cd(II) ions with coordination numbers four and six are bridged by two iodide anions. Cd 1 and Cd2 have distorted octahedral CdI2N 4 and tetrahedral CdI4 geometries, respectively.Weak intermolecular hydrogen bonds H⋯I and H⋯O stabilize the supramolecular network. © 2011 Verlag der Zeitschrift für Naturforschung, Tübingen.

DOI： 10.1515/znb-2011-1106

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A convenient and successful one-pot preparation of the 2- aminobenzoselenazoles via the phenylselenoureas has been accomplished by the copper-catalyzed ligand-free reaction of the 2-iodoanilines and isoselenocyanates; the intermediate, selenoureas, were isolated, and quantitatively transformed into the selenazaoles. © 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2010.11.092

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Reaction of 2-(aminomethyl)pyridine with selenium dioxide leads to the formation of imidazo[1,5-a]pyridine (2-azaindolizin6) skeleton in a single step. The major products of the reactions are 3-(2-pyridyl)imidazo[1,5-a]pyridine, bis[3-(2-pyridyl) imidazo[1,5-a]pyridin-1-yl] selenide, or the corresponding diselenide depending upon the reaction conditions. The structures of these selenium-bridged imidazo[1,5-a]pyridine derivatives are disclosed by X-ray crystal structural analyses. For the diselenide, the unusual dihedral angle CSeSeC of 56.0° was observed indicating π-π intramolecular interaction between the fused six-membered rings. © 2011 The Chemical Society of Japan.

DOI： 10.1246/cl.2011.449

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o-Ethynylbenzyl phenyl selenides regioselectively reacted with trifluoromethanesulfonic acid to afford the (Z)-1-methylidene-2-phenyl-1,3- dihydro-1H-benzo[c]selenophenium salts as the major products during the 5-exo-dig mode cyclization in good yields together with minor E isomers. The structure of the major (Z)-selenophenium salt was established by the single crystal X-ray crystallographic analysis using a tert-butyl derivative. © 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2010.07.160

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The intramolecular cyclizations of four types of dibenzyl chalcogenols, which contained one or two ethynyl groups, were carried out. Either the double 5-exo or 6-endo-dig mode ring closure reaction regio- and stereoselectively proceeded to give the corresponding symmetrical bis(benzoc1chalcogeno- phene) or bis(isochromene) derivatives from the dibenzyl chalcogenols having a diyne moiety. In contrast, the regioselective tandem 5-exo-dig mode intramolecular ring closure reactions of dibenzyl thiol and selenol having a mono-yne into a triple bond gave the trans-biisobenzothiophene and selenophene as the sole product. However, the similar cyclization of dibenzyl tellurol proceeded in both tandem 5-exo and 6 endo dig modes to afford the trans biisobenzotellurophene and ditellurachrysene in good yields with the ratio of 1:1. The X-ray structural analysis of these novel compounds is also presented. © 2010 Elsevier Ltd.

DOI： 10.1016/j.tet.2010.04.101

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The first examples of stable spirodiazaselenurane and spirodiazatellurane were synthesized by oxidative spirocyclization of the corresponding diaryl selenide and telluride and were structurally characterized. X-ray crystal structures of the spirodiazaselenurane and spirodiazatellurane suggest that the structures are distorted trigonal bipyramidal (TBP) with the electronegative nitrogen atoms occupying the apical positions and two carbon atoms and the lone pair of Se/Te occupying the equatorial positions. Interestingly, the spirodiazatellurane underwent spontaneous chiral resolution during crystallization, and the absolute configurations of its enantiomers were confirmed by single-crystal X-ray analyses. A detailed mechanistic study indicates that the cyclization to spirodiazaselenurane and spirodiazatellurane occurs via selenoxide and telluroxide intermediates. The chalcogenoxides cyclize to the corresponding spiro compounds in a stepwise manner via the involvement of hydroxyl chalcogenurane intermediates, and the activation energy for the spirocyclization reaction decreases in the order S > Se > Te. In addition to the synthesis, characterization, and mechanism of cyclization, the glutathione peroxidase (GPx) mimetic activity of the newly synthesized compounds was evaluated. These studies suggest that the tellurium compounds are more effective as GPx mimics than their selenium counterparts due to the fast oxidation of the tellurium center in the presence of peroxide and the involvement of an efficient redox cycle between the telluride and telluroxide intermediate. © 2010 American Chemical Society.

DOI： 10.1021/ja908080u

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Several types of novel isotellurochromenium salt derivatives (210) were prepared from the isotellurochromenes (1). The isotellurochromenium tetrafluoroborates (2), triflates (35), tosylates (6) and mesylates (7) are telluronium salts, and the dihalogenoisotellurochromenes (810) are telluranes. The molecular structures of the isotellurochromenium tosylate (6a) and the dichloroisotellurochromene (8a) were characterized by an X-ray crystallographic analysis using the 3-tert-butyl derivatives. © 2010 The Japan Institute of Heterocyclic Chemistry Received.

DOI： 10.3987/COM-09-S(S)124

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Heating of o-ethynylanilines with isoselenocyanates directly resulted in the 6-exo-dig mode ring-closure reaction of the adducts to give the (Z)-2-imino-4-methylene-3-selenaquinolines in moderate to good yields. Based on this convenient, solvent-free, catalyst-free method, several 3-selenaquinoline derivatives (3,1-benzoselenazines) were easily obtained in one pot. Successful application of the microwave-assisted synthesis of these compounds was also investigated. © Georg Thieme Verlag Stuttgart - New York.

DOI： 10.1055/s-0030-1258171

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(Chemical Equation Presented) The p(Z)-π(Ar) conjugations must operate fully in the ground states of 9-(arylchalcogenyl)triptycenes (p-YC 6H4ZTpc:1 (Z = O), 2 (Z = S), 3 (Z = Se), and 4 (Z = Te)), where the p-YC6H4 group is placed in the bisected area between two phenyl planes of the triptycyl group with the parallel orientation. The ground-state geometries, which we call (A: pl), are confirmed by X-ray analysis. However, the conjugations never operate in the transition states between (A: pl) and/or the topomeric structures (A′: pl′), where the Z-CTpc bond is perpendicular to the plane. The site-exchange processes correlate to the conjugations. Temperature-dependent 1H NMR spectra are analyzed for 2 and 3 to demonstrate the effective p(Z)-π(Ar) conjugations. The activation energies for the interconversion between (A: pl) and (A′: pl′) (GR: gear process) were obtained for 2 (ΔG ‡GR(2)) and 3 (ΔG‡GR(3)). ΔG‡GR(3) correlate well with ΔG‡GR(2), and ΔG ‡GR(2) are well analyzed by the Hammett-type dual parameters. ΔG‡GR(2) and ΔG ‡GR(3) are demonstrated to be controlled by the resonance interaction of the p(Z)-π(C6H4)-p(Y) conjugations. QC calculations are performed on the ground and exited states of 1-4, which clarify the effective p(Z)-π(C6H4)-p(Y) conjugations for Z of heavier atoms. © 2009 American Chemical Society.

DOI： 10.1021/jo900488r

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The three main parts; i.e., the preparations, structures and reactions of the 1-benzotelluropyryli- um salts are described. The synthetic workup has been achieved by transformation from the tel-lurochromones, which were simply prepared by the reaction of the o-bromophenyl ethynyl ketones with sodium hydrogen telluride (NaHTe). The synthetic method for the preparation of the tellurochromones is based on the intramolecular ring closure of a tellurol moiety into a triple bond. The study shows that these salts, although being stable compounds, are highly reactive with various nucleophiles including OMē, diethylamine, CN̄, an active methylene compound and Grignard reagents, and also hydrogenation and hydrolysis to afford the successful corresponding 2- or 4-substituted tellurochromene derivatives. The chemistry of the 1-benzoselenopyrylium salts is also described. The thermolysis of the 2-azidoselenochromenes, which were easily obtained by the reaction of the selenopyrylium salts with sodium azide, resulted in a ring expansion to produce the novel stable 1,3-benzoselenazepines. X-ray structural analyses of the terf-butyltelluro- and selenopyrylium salts are also reported.

DOI： 10.5059/yukigoseikyokaishi.67.714

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9-(Arylselanyl)triptycenes (1: p-YC6H4SeTpc) should supply the planar structure (pl) around the p-YC6H4Se (ArSe) group in the ground state, irrespective of the p-Y substituents. 1 with Y = H (a), NMe2 (b), OMe (c), Cl (d), CN (e) and NO2 (f) are prepared. Structures of 1a-d and 1f are determined by X-ray analysis and dynamic 1H NMR spectroscopy is applied to 1a, 1c, 1e and 1f. For convenience of discussion, the structure of 1 is defined as follows: a conformer around the triptycyl group in 1 is called A where the Se-CAr bond is placed in the bisected area between two phenyl planes of the triptycyl group and it is B where the bond is on a phenyl plane of the triptycyl group. A conformer for the Ar group is named pl where the Se-CTpc bond is on the Ar plane, while it is pd if the bond is perpendicular to the plane. The structure of 1 is confirmed to be (A: pl) in the ground state by X-ray analysis. 1 (A: pl) changes to the equivalent one via a transition state of 1 (B: pd) (the gear process). The activation energies are determined by dynamic 1H NMR spectroscopy: the values are 36.4, 41.6, 42.3 and <34 kJ mol-1 for 1a, 1e, 1f and 1c, respectively. The MP2 level of calculations reproduced the observed values: they are evaluated to be 34, 39, 40 and 29 kJ mol-1 for 1a, 1e, 1f and 1b′ (Y = NH2), respectively, where 1b′ is employed in place of 1c. Another process (the isolated rotation process) is also operating for the interconversion of 1 (A: pl), which proceeds via1 (A: pd). The activation energies for the process are predicted to be 25, 30, 30 and 20 kJ mol-1 for 1a, 1e, 1f and 1b′, respectively, at the MP2 level. The results demonstrate that (A: pl) is the global minimum in 1: the 1 (A: pl) structure is well established for all Y examined in the ground state. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2009.

DOI： 10.1039/b817949b

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Publishing type：Research paper (scientific journal)  

1-Cyano-3-(2-pyridinecarboxamido)-2-(2-pyridiyl)indolizine (2) was readily synthesized by the one-pot reaction of 2-(cyanomethyl)pyridine (1a) with selenium dioxide. The reaction of 3- or 4-(cyanomethyl)pyridines (1b,c) under the same reaction conditions gave 2,3-bi(3-pyridyl)-2-butenedinitrile (3b) and 2,3-bi(4-pyridyl)-2-butenedinitrile (3c), respectively. The indolizine 2 (L-H) reacted with Ni(NO3)2·6H2O in ethanol to produce the NiL2 complex (4). The structure was determined by X-ray crystallography. © 2008 The Japan Institute of Heterocyclic Chemistry.

DOI： 10.3987/COM-07-11197

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Language：English   Publishing type：Research paper (scientific journal)  

1-Mesityl-1,3-dihydro-imidazole-2-selone, (seimMes)H, may be obtained from 1-mesitylimidazole via (i) deprotonation with BunLi, (ii) treatment with elemental selenium, and (iii) addition of HCl(aq). Structural characterization of (seimMes)H by X-ray diffraction demonstrates that the compound exists as the selone rather than selenol tautomer, a result that is in accord with DFT calculations. Solutions of (seimMes)H are oxidized by air to give bis(1-mesitylimidazol-2-yl) diselenide, (seimMes)2. A corresponding investigation of (seimMe)H demonstrates that, in contrast to a previous report, the selenium analogue of methimazole exists in the selone form with a structure analogous to that of methimazole. 1H and 77Se NMR studies demonstrate that the (seimR) groups of the selone (seimR)H and diselenide (seimR)2 undergo facile exchange on the NMR time scale. © 2006 American Chemical Society.

DOI： 10.1021/ja063168e

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Language：English   Publishing type：Research paper (scientific journal)  

A new tripodal ligand that features three selenium donors, namely the tris(2-seleno-1-mesitylimidazolyl)hydroborato ligand, [TseMes], has been constructed via the reaction of KBH4 with 1-mesitylimidazole-2- selone; comparison of the IR spectroscopic data of [TseMes]Re(CO) 3 with those of a variety of related LRe(CO)3 complexes demonstrates that the [TseMes] ligand is more strongly electron donating than Cp, Cp*, [Tp], [TpMe2] and [Tm Mes] ligands. © The Royal Society of Chemistry 2006.

DOI： 10.1039/b608078b

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Publishing type：Research paper (scientific journal)  

Deamination reactions of 1-alkyl-9-aminomethyltriptycenes (alkyl = Me, Et, i-Pr, and t-Bu) and 9-(1-aminoethyl)-1-methyltriptycene were performed in CHCl 3 and in AcOH, and product distributions were studied. The results suggest that the loss of N 2 from a primary alkanediazonium ion predominantly takes place concomitantly with participation of a C-H bond of the neighboring 1-alkyl group to form a nonclassical cationic species with a three-center two-electron bonding, while the loss of N 2 from a secondary alkanediazonium ion occurs spontaneously to form a secondary carbocation. Solvent effects (CHCl 3 vs AcOH) are explained in terms of lower nucleophilicity/basicity of the AcO - in AcOH than in CHCl 3 due to solvation. © 2006 The Chemical Society of Japan.

DOI： 10.1246/bcsj.79.1585

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9-Triptycylallene (1) was synthesized by LiAlH 4 reduction of 1-(9-triptycyl)-2-propynyl methanesulfonate (7), and three 3-substituted derivatives of 1 were also obtained by reacting compound 7 with appropriate metal reagents. LiAlH 4 reduction of 1,3-di(9-triptycyl)-2-propynyl methanesulfonate (10) gave 1,3-di(9-triptycyl)propyne (12). The molecular structures of some of the allenes and of the propyne were determined by X-ray crystallography. As well, the allenes and some of the related compounds were characterized by NMR spectroscopy. © 2006 The Chemical Society of Japan.

DOI： 10.1246/bcsj.79.1293

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Publishing type：Research paper (scientific journal)  

Static and dynamic stereochemistry of several tris(9-triptycyl)stannane derivatives Tp3SnX (X = H, halogens, and alkyl groups) were studied. X-ray crystallography of the bromo and methyl compounds showed that the Sn atom was fundamentally tetrahedral and that the three Tp groups meshed with each other like bevel gears and formed a near-C3 chiral conformation. The rate constants for enantiomerization of the chiral conformation in solution could be obtained by the lineshape analysis of the aromatic proton signals, even when a direct probe for enantiomerization such as a benzyl group was absent. The energy barrier to enantiomerization decreased as the substituent X became bulkier, suggesting that the ground state is more destabilized than the transition state upon introduction of a bulkier group. © 2005 The Chemical Society of Japan.

DOI： 10.1246/bcsj.78.487

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Publishing type：Research paper (scientific journal)  

DOI： 10.1021/JO050251W

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Language：English   Publishing type：Research paper (scientific journal)  

X-ray analysis of bis(p-fluorophenyl)methyl cation bearing a 2,6-bis(p-tolyloxymethyl)benzene ligand showed a symmetrical structure (10-C-5) where the two C-O distances are identical, although the distance (2.690(4) Å) is longer than those (2.43(1) and 2.45(1) Å) of 1,8-dimethoxy-9-dimethoxymethyl-anthracene monocation, which was recently reported by us. However, X-ray analysis of the more stable aromatic xanthylium cation with the same benzene ligand showed the tetracoordinate carbon structure where only one of the two oxygen ligands is coordinated with the central carbon atom. These results clearly indicate that the carbocations (10-C-5) bearing the sterically flexible benzene ligand were quite sensitive to the electronic effect on the central carbon atom. The electron distribution analysis by accurate X-ray measurements and the density functional calculation on the initially mentioned bis(p-fluorophenyl)methyl cation clearly show that the central carbon atom and the two oxygen atoms are bonded even if the bond is weak and ionic based on the small value of the electron density (ρ(r)) and the small positive Laplacian value (∇2ρ(r)) at the bond critical points. © 2005 American Chemical Society.

DOI： 10.1021/ja043802t

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Language：English   Publishing type：Research paper (scientific journal)  

A variety of hexaorganotellurium compounds, Ar6-n(CH 3)nTe [Ar = 4-CF3C6H4, n = 0 (1a), n = 1 (3a), n = 2 (trans-4a and cis-4a), n = 3 (mer-5a), n = 4 (trans-6a); Ph, n = 0 (1b), n = 1 (3b), n = 2 (trans-4b); 4-CH3C 6H4, n = 0 (1c), n = 1 (3c), n = 2 (trans-4c), n = 4 (trans-6c); 4-BrC6H4, n = 0 (1d)] and Ar5(R)Te [Ar = 4-CF3C6H4, R = 4-CH3OC 6H4 (8); Ar = 4-CF3C6H4, R = vinyl (9), Ar = Ph, R = vinyl (10), Ar = 4-CF3C6H 4, R = PhSCH2 (11), Ar = Ph, R = PhSCH2 (12), Ar = 4-CF3C6H4, R = nBu (13)] and pentaorganotellurium halides, Ar5TeX [Ar = 4-CF3C 6H4, X = Cl (2a-Cl), X = Br (2a-Br); Ar = Ph, X = Cl (2b-Cl), X = Br (Zb-Br); Ar = 4-CH3C6H4, X = Cl (2c-Cl), X = Br (2c-Br); Ar = 4-BrC6H4, X = Br (2d-Br)] and (4-CF3C6H4)4(CH3)TeX [X = Cl (trans-7a-Cl) and X = Br (trans-7a-Br)] were synthesized by the following methods: 1) one-pot synthesis of 1a, 2) the reaction of SO 2Cl2 or Br2 with Ar5Te Li + generated from TeCl4 or TeBr4 with five equivalents of ArLi, 3) reductive cleavage of Ar6-m(CH 3)mTe (m = 0 or 2) with KC8 followed by treatment with CH3I, 4) valence expansion reaction from low-valent tellurium compounds by treatment with KC8 followed by reaction with CH3I, 5) nucleophilic substitution of Ar6-y-z(CH 3)zTeXy-z (X=Cl, Br, OTf; z = 0, 1; y= 1, 2) with organolithium reagents. The scope and limitations and some details for each method are discussed and electrophilic halogenation of the hexaorganotellurium compounds is also described.

DOI： 10.1002/chem.200305260

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During the course of attempts at synthesis of N-phenyl-N-9- triptycylhydroxylamine (1), we found that the reaction of N-9- triptycylhydroxylamine (5) with benzenediazonium-2-carboxylate afforded 3-(2-carboxyphenyl)-1-(9-triptycyl)-triazene 1-oxide (6), the structure of which was confirmed by X-ray crystallography. Oxidation of N-(9-triptycyl)aniline (4) with mCPBA gave phenyl 9-triptycyl nitroxide (7) and N-(9-triptycyl)-1,4- benzoquinonimine (8) in small yields. Reduction of 7 with phenylhydrazine gave 1, and O-ethylation of 1 gave O-ethyl-N-phenyl-N-9-triptycylhydroxylamine (2). Results of X-ray crystallography for compounds 2, 4, 7, and 8 and results of dynamic NMR studies for 1, 2, and 8 are presented. In compound 8, Tp-N rotation and C=N topomerization took place on the NMR timescale at high temperatures above 60 °C, and the energy barriers to both processes were obtained. In compounds 1 and 2. dynamic NMR behavior was observed at very low temperatures below ca. -50 °C, and the energy barriers to the respective processes could not be determined except for those related to "Ph-passing".

DOI： 10.1246/bcsj.77.2273

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1H dynamic NMR study of benzyltris(9-triptycyl)stannane (4) using two probes, the benzylic methylene and the aromatic peri-proton signals, revealed that the enantiomerization of the chiral conformers took place with ΔG‡ of 64.2 kJ mol-1 at 300 K.

DOI： 10.1246/cl.2003.964

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The static and dynamic stereochemistry of N-9-triptycylhydroxylamine derivatives (TpNHOR) with O-benzyl (3), O-ethyl (4), and O-phenyl (5) groups were studied. X-ray crystallographic analysis revealed that these compounds reside in a chiral conformation, with the Tp-N-O-R dihedral angle of 140-160°. Dynamic NMR studies of 3 and 4 show the presence of two separate stereomutation processes: chirality reversal (enantiomer interconversion) and rotation of the Tp-N bond with retaining the chirality, the latter having a lower energy barrier. Compound 5 gave solely information on the Tp-N rotation because of the lack of a probe for chirality reversal.

DOI： 10.1246/bcsj.76.825

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Static and dynamic stereochemistry of N-alkyl, O-alkyl, and N,O-dialkyl derivatives of N-(1,4-dimethyl-9-triptycyl)hydroxylamine were studied. X-ray crystallographic analysis revealed that an N-alkyl derivative adopts R*-(-sc)* conformation while N,O-dialkyl derivatives adopt R*-ap conformation. In solufion, stereomutation was almost frozen on the NMR timescale at ca. -60 °C. The same conformer as found in the crystal was the major conformer in solution in each compound, and a small amount of a second conformer was found in equilibrium with the major one for the N-alkyl and N,O-dialkyl derivatives. The stereomutation was interpreted in terms of diastereomerization and enantiomerization, and the 1H NMR lineshape analysis afforded the activation parameters for these processes.

DOI： 10.1246/bcsj.76.1801

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Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

Hexavalent tellurium compounds, Ar&lt;SUB&gt;5&lt;/SUB&gt;(CH&lt;SUB&gt;3&lt;/SUB&gt;)Te, Ar&lt;SUB&gt;4&lt;/SUB&gt;(CH&lt;SUB&gt;3&lt;/SUB&gt;)&lt;SUB&gt;2&lt;/SUB&gt;Te, and Ar&lt;SUB&gt;2&lt;/SUB&gt;(CH&lt;SUB&gt;3&lt;/SUB&gt;)&lt;SUB&gt;4&lt;/SUB&gt;Te (Ar=4-CF&lt;SUB&gt;3&lt;/SUB&gt;C&lt;SUB&gt;6&lt;/SUB&gt;H&lt;SUB&gt;4&lt;/SUB&gt;, Ph, 4-CH&lt;SUB&gt;3&lt;/SUB&gt;C&lt;SUB&gt;6&lt;/SUB&gt;H&lt;SUB&gt;4&lt;/SUB&gt;), were synthesized by the reaction of Ar&lt;SUB&gt;2-n&lt;/SUB&gt;(CH&lt;SUB&gt;3&lt;/SUB&gt;)&lt;SUB&gt;n&lt;/SUB&gt;Te (n=0–1) or Ar&lt;SUB&gt;3-m&lt;/SUB&gt;(CH&lt;SUB&gt;3&lt;/SUB&gt;)&lt;SUB&gt;m&lt;/SUB&gt;Te&lt;SUP&gt;+&lt;/SUP&gt;X&lt;SUP&gt;-&lt;/SUP&gt; (m=0–2) with KC&lt;SUB&gt;8&lt;/SUB&gt; followed by the treatment with CH&lt;SUB&gt;3&lt;/SUB&gt;I.

DOI： 10.1246/cl.2002.288

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The regioselective and stereospecific intramolecular ring closure reactions of o-ethynylbenzyl tellurols 5A and o-ethynylbenzyl selenols 5B, which were readily generated by the reaction of the o-ethynylbenzyl bromides 4 with sodium hydrogen telluride (NaHTe) or sodium hydrogen selenide (NaHSe), produced the isotellurochromenes 6A and isoselenochromenes 6B together with (Z)-1-methylidene-2-telluraindans 7A and (Z)-1-methylidene-2-selenaindans 7B, respectively. The obtained isochromenes 6A and 6B were transformed into the corresponding 2-benzotelluropyrylium tetrafluoroborates 9A and 2-benzoselenopyrylium tetrafluoroborates 9B by treatment with triphenylcarbenium tetrafluoroborate (Ph3C+BF4 −) in excellent yields, respectively. An X-ray structural analysis of the tert-butyl derivatives 9Ac and 9Bc is also described. © 2002 The Royal Society of Chemistry.

DOI： 10.1039/b111045b

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Publishing type：Research paper (international conference proceedings)  

DOI： 10.1080/10426500213441

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Language：English   Publishing type：Research paper (scientific journal)  

The potassium ion intercalated in graphite results in unique reactivity of Ar5Te-K+C8 (1), formed by cleavage of one of the Te-C(Ar) bonds of Ar6Te (see scheme) by KC8. Thus, 1 reacted quantitatively with CH3I to give Ar5TeCH3, which was not obtainable from Ar5Te-Li+. The Te-CH3 bond of Ar5TeCH3 is cleaved in preference to the Te-C(Ar) bonds, and formation of Ar4Te(CD3)2 suggests the intermediacy of the hypervalent dianion Ar4Te2-.

DOI： 10.1002/1521-3773(20010716)40:14<2674::AID-ANIE2674>3.0.CO;2-H

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A novel family of organochalcogens, Ph5TeX (X = Cl, Br), was readily obtained by the halogenation of Ph5TeLi, which was prepared by reaction of 5 equiv of PhLi with 1 equiv of TeCl4 or TeBr4; Ph5TeF was obtained by treating the bromide with KF. The Te atom is in the highest oxidation state, Te(VI), and is covalently bonded to the halogen atom, in contrast to the ionic bonding in R3TeIVX.

DOI： 10.1021/om001075e

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Publishing type：Research paper (scientific journal)  

The reaction of pentaphenyltellurium chloride 2 with silver perchlorate afforded the pentaphenyltelluronium salt, Ph5Te+ClO4-, (1b), and treatment of 2 with silver triflate and sodium tetrakis{3,5-bis(trifluoromethyl)phenyl}borate provided Ph5Te+[3,5-(CF3)2C6H 3]4B- (1c), which were isolated as stable yellow solids. X-ray crystallographic analysis of the hypervalent telluronium salts revealed square pyramidal geometry around the tellurium, which are rare examples for penta-substituted main group element compounds.

DOI： 10.1002/hc.1057

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DOI： 10.1021/ja992828v

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Azabisomocine derivatives having a pentavalent bismuth and a nitrogen at 1,5-position were synthesized. The X-ray structural analysis reveals that these compounds have hexacoordinate distorted octahedral geometry which is caused by transannular bond formation between the bismuth and the nitrogen.

DOI： 10.1246/cl.1999.861

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Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/10426509808545993

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Publishing type：Research paper (scientific journal)  

Te(C6H4-CF3)6 1a was obtained by the unique one-pot reaction of LiC6H4-4-CF3 with TeCl4. The Te atom resides in the highest oxidation state (Te(VI)) having six C-Te bonds in 1a. Compound la is extremely thermally stable and not light sensitive unlike tetraorganotellurium compounds. The X-ray crystallographic analysis of 1a revealed a rare example of approximately T(h) molecular symmetry.

DOI： 10.1016/S0040-4020(97)00552-8

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Publishing type：Research paper (scientific journal)  

The one-pot reaction of sterically hindered hydrazones with tellurium dichloride or tellurium tetrahalide in the presence of triethylamine in benzene afforded Δ3-1,3,4-telluradiazolines 1, a novel heterocycle, via 1,3-dipolar cycloaddition of telluroketones and diazo compounds, both generated in situ. The molecular structure of 1a was established by X-ray crystallographic analysis. The photolysis of In led to instant and quantitative formation of the corresponding azine 8a, whereas the thermolysis of in in the solid state afforded the corresponding retrocyclization products.

DOI： 10.1016/S0040-4020(97)00498-5

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The solid-state thermolysis of a sterically hindered Δ3-1,3,4-telluradiazoline 2 afforded products resulting from intermediary tellone 1 and diazo compound 8 formed by retrocyclization, whereas the flash vacuum thermolysis of 2 led to isolation of tellone 1 as green needles. The spontaneous dimerization of 1 thus obtained occurred in the solid state to give the corresponding 1,3-ditelluretane 10, which underwent the thermal cycloreversion in solution to regenerate pure tellone 1.

DOI： 10.1016/S0040-4039(97)00377-8

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Treatment of a stable telluroketone with W(CO)5·thf affords the title compound, the X-ray crystal structure of which shows η1,σ-complexation and the trans influence of the weakly coordinated telluroketone; the regeneration of a 'free' telluroketone by ligand exchange of the complex under mild conditions is also reported.

DOI： 10.1039/CC9960000123

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Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.199626601

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Language：English   Publishing type：Doctoral thesis  

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Publishing type：Research paper (scientific journal)  

DOI： 10.1246/CL.1995.103

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Publishing type：Research paper (scientific journal)  

A novel tellurium containing heterocycle, 1,4,2-oxatellurazole, was characterized by X-ray crystallographic analysis which showed a remarkably small C-Te-C bond angle (79.4°), and its 1,3-dipolar cycloreversion is discussed. © 1994, Taylor & Francis Group, LLC. All rights reserved.

DOI： 10.1080/10426509408021877

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Publishing type：Research paper (scientific journal)  

DOI： 10.1246/CL.1994.1691

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DOI： 10.1246/CL.1993.1047

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Publishing type：Research paper (scientific journal)  

DOI： 10.1021/ja00068a088

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Applicant：学校法人北里研究所

Application no：特願2009-210669  Date applied：11 9 2009

Announcement no：特開2011-057637  Date announced：24 3 2011

J-GLOBAL

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Applicant：東京化成工業株式会社

Application no：特願2000-074902  Date applied：14 2 2000

Announcement no：特開2001-226348  Date announced：21 8 2001

J-GLOBAL

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