Highly Efficient and Chemoselective Tertiary and Secondary Benzylation of Thiols Catalyzed by Indium(III) Triflate
作者:Krzysztof Kuciński、Grzegorz Hreczycho
DOI:10.1002/ejoc.201701007
日期:2017.10.10
We have developed a highly efficient method for the chemoselective nucleophilicsubstitution of tertiary and secondary benzylic alcohols with aliphatic and aromatic thiols in the presence of catalytic amounts of indium(III) triflate under mild conditions. A broad range of unsymmetrical sulfides were synthesized in excellent isolated yields (89–99 %) by using this approach.
Pummerer Cyclization Revisited: Unraveling of Acyl Oxonium Ion and Vinyl Sulfide Pathways
作者:Xin Li、Rich G. Carter
DOI:10.1021/acs.orglett.8b02059
日期:2018.9.21
Two viable pathways (vinyl sulfide and acyl oxoniumion) for the Pummerer cyclization have been unraveled that expand the reaction scope and capabilities. Use of Brønsted-enhanced Lewis acidity was key to realization of the vinyl sulfide pathway, whereas selective complexation of the sulfur lone pair facilitated the unprecedented acyl oxoniumion pathway. Preliminary mechanistic investigations support
Kinetics of the Thermal Decompositions of Diaryl and Dialkyl Disulfides
作者:Tokuji Miyashita、Minoru Matsuda、Masashi Iino
DOI:10.1246/bcsj.48.3230
日期:1975.11
observed that the rates of the decompositions for diaryl disulfides are increased by p-substituents (CH3O>Cl\simeqCH3>H) and that that of di-t-butyl disulfide is comparable to diaryl disulfides, whereas, di-n-butyl disulfide shows no decomposition under these conditions. A reaction scheme of the decomposition including induced decomposition is proposed from the kinetic results and product analysis. Moreover
A new protocol was developed to synthesize (enantioenriched) thioethers and selenoethersfrom (chiral) benzylic trimethylammonium salts and di(hetero)aryl disulfides or diselenides. These syntheses were promoted by the presence of weak base and did not require the use of any transition metal, and resulted in the target products with good to excellent yields (72–94%). Using quaternary ammonium salts