Ryu Sato

First direct synthesis of 4,8-dialkylbenzo[1,2-d;4,5-d′]bis[1,2,3]trithioles and 6,10-dialkyl[1,2,3]trithiolo[5,4-h]benzopentathiepins from 1,4-dialkyl-2,3,5,6-tetrabromobenzenes

Abstract New cyclic polysulfides, 4,8-dialkylbenzo[1,2-d;4,5-d′]bis[1,2,3]-trithioles ( 2 ) and 6,10-dialkyl[1,2,3]trithiolo[5,4-h]benzopentathiepins ( 3 ), were directly synthesized by nucleophilic substitution of 1,4-dialkyl-2,3,5,6-tetrahalobenzenes ( 1 ) with elemental sulfur in liquid ammonia.

Synthesis, structure, and one-electron redox reactions of 4,7-disubstituted benzotrichalcogenoles containing sulfur and/or selenium atoms

Abstract Stable 4,7-disubstituted benzotrichalcogenoles containing sulfur and/or selenium atoms in the five-membered ring were systematically and selectively prepared in good yields by reaction of the corresponding benzodichalcogenastannoles, a synthetic equivalent of benzenedichalcogenols, with an S 1 or Se 1 source. Characterization of these new trichalcogenole frameworks was performed by multi-nuclear NMR studies and X-ray crystallographic analyses. The cyclic voltammograms of the trichalcogenoles showed well-defined reversible electrochemical redox couples with low oxidation potential. Novel radical ions were isolated in quantitative yields in the one-electron oxidation of the trichalcogenoles with one equivalent of NOPF 6 as a one-electron oxidant. The structures of the radical cation salts were analyzed by 31 P-NMR and EPR spectroscopies, and elemental analyses. The salts underwent one-electron reduction on treatment with one equivalent of samarium(II) iodide to give the neutral starting trichalcogenoles quantitatively.

Preparation and conformational analysis of 6,10-disubstituted [1,2,3]trithiolo[h]benzopentathiepin monooxides

6,10-Diethyl[1,2,3]trithiolo[ h ]benzopentathiepin was oxidized with m CPBA (1 eq.) to produce four monooxides, 6,10-diethyl[1,2,3]trithiolo[ h ]benzopentathiepin 8-oxides and 6,10-diethyl[1,2,3]trithiolo[ h ]benzopentathiepin 7-oxides. The structure of the four monooxides obtained was determined by X-ray crystallography. The activation parameters, ΔG ≠ , ΔH ≠ , and ΔS ≠ of these compounds with respect to the inversion of their pentathiepin rings were determined by the results of 1 H-NMR spectroscopy.

Novel photochemical ring contraction of 1,4,7,10-tetraisopropyldibenzo[c,g][1,2,5,6]tetrachalcogenocins: efficient synthesis, structure, and redox reactions of 1,4,6,9-tetraisopropylchalcogenanthrenes

Abstract 1,4,7,10-Tetraisopropyldibenzo[c,g][1,2,5,6]tetrachalcogenocins, which were readily synthesized from 4,7-diisopropyl-2,2-dimethyl-1,3,2-benzodichalcogenastannoles, underwent selective ring contraction under irradiation with a high-pressure mercury lamp to give the corresponding 1,4,6,9-tetraisopropylchalcogenanthrenes in moderate yields. Facile one-electron redox reactions were observed between the chalcogenanthrenes and the corresponding stable chalcogenanthrenium radical cations by chemical or electrochemical treatment.

Photolytic preparation, structure, and electrochemical properties of thianthrene derivatives bearing trithiole and dithian rings

Abstract Photolytic desulfurization and ring-contraction reactions of diethyl benzotrithiole and tetraethyl dibenzotetrathiocin proceeded without a desulfurization reagent such as trialkyl phosphite by irradiation with a 100 W high-pressure Hg lamp in CH2Cl2 under Ar to produce tetraethyl thianthrene. By means of the photolysis, the thianthrene derivatives bearing trithiole and dithian rings on both sides of thianthrene were obtained in good yields.

Chemistry on benzopentathiepin reactions of benzopentathiepin with aromatic compounds in the presence of lewis acid

Benzopentathiepin (BPT) reacted with many aromatic compounds such as benzene, 1,4-dimethylbenzene, and naphthalene in the presence of Lewis acid to give various thianthrenes in moderate yields. BPT was found to serve as a 1,4-dication synthon

New tellurium containing five-membered trichalcogenaheterocycles fused to benzene ring: A convenient method for transformation of dichalcogenatelluroles into novel tetrachalcogenocins

Abstract Stable benzene-fused 5-membered trichalcogenaheterocycles containing sulfur, selenium, and tellurium 2 were newly prepared by the reactions of corresponding 4- tert -butyldimethylsilyl-2,2-dimethylbenzo[1,2- d ][1,3,2]dichalcogenastannoles 1 with tellurium tellurium tetrachloride in good yields. These new 5-membered heterocycles containing tellurium were readily transferred to 8-membered tetrachalcogenocins 4,5 on treatment with aqueous tetrahydrofuran in moderate yields.

Novel multi-chalcogen ring systems with three different chalcogen atoms: synthesis, structure and redox property of five-membered trichalcogenaheterocyclesElectronic supplementary information (ESI) available: satisfactory characterizing data for all the new compounds. Typical experimental procedure, physical and spectroscopic data of all the new compounds and ORTEP view of 2d. See http://www.rsc.org/suppdata/cc/b2/b205445k/

The molecular structure of novel five-membered trichalcogenaheterocycles with three different chalcogen atoms, sulfur, selenium and tellurium, has been determined by crystallographic studies.

Novel addition of 5H-benzo[f]-1,2,3,4-tetrathiepin and 6H-benzo[g]-1,2,3,4,5-pentathiocin to alkenes in the presence of BF3.OEt2

Abstract The treatment of 5H-benzo[f]-1,2,3,4-tetrathiepin (BTTP) or 6H-benzo[g]-1,2,3,4,5-pentathiocin (BPTC) with alkenes in the presence of BF 3 ·OEt 2 afforded trans adducts, 2,3-disubstituted benzo-1,4,5-trithiocanes ( 1 ), which further reacted with alkenes to give cis adducts, 2,3-disubstituted benzo-1,4-dithiepanes ( 2 ).

Convenient synthesis of 1,2,4-benzotrithiins from benzopentathiepin with phosphorus ylide

Abstract Novel 1,2,4-benzotrithiins were synthesized in satisfactory yields by treatment of benzopentathiepin with alkylidenephosphoranes. In this reaction, benzopentathiepin was found to serve as a 1,5-dipole synthon.