Investigation of steric and electronic effects in the copper-catalysed asymmetric oxidation of sulfides
作者:Graham E. O'Mahony、Kevin S. Eccles、Robin E. Morrison、Alan Ford、Simon E. Lawrence、Anita R. Maguire
DOI:10.1016/j.tet.2013.08.063
日期:2013.11
in the copper-catalysed asymmetricoxidation of aryl benzyl, aryl alkyl and alkyl benzyl sulfides have been investigated. The presence of an aryl group directly attached to the sulfur is essential to afford sulfoxides with high enantioselectivities, with up to 97% ee for 2-naphthyl benzyl sulfoxide, the highest enantioselectivity achieved to date for copper-catalysed asymmetric sulfoxidation. In contrast
2,6-Dicarboxypyridinium chlorochromate (2,6-DCPCC) was found to be an efficient reagent for the conversion of thiols to disulfides and sulfides to sulfoxides under neutral and anhydrous conditions in good to excellent yields. Selective oxidation of thiols in the presence of sulfides at room temperature is also observed with this reagent.
An Efficient Synthesis of Unsymmetrical Sulfides Using Liquid-Liquid Phase-Transfer Catalysis
作者:Toshio Takido、Kunio Itabashi
DOI:10.1055/s-1987-28085
日期:——
The reaction between alkyl ethaneimidothioate hydrohalides (1-alkylthioethaniminium halides) and organic halides gives unsymmetrical sulfides in good yields under liquid-liquid phase-transfer conditions.
Indium-catalyzed Direct Conversion of Dibenzyl Ethers to Dibenzyl Sulfides Using Elemental Sulfur and a Hydrosilane and Its Application to the Preparation of Benzyl Selenides
compound, a hydrosilane and an easily handled form of elemental sulfur (S8) that effectively and directly catalyzes the sulfidation of dibenzyl ethers to produce dibenzyl sulfides. This system could also be applied to selenium in a straightforward conversion to dibenzyl selenides.
Convenient and robust one-pot synthesis of symmetrical and unsymmetrical benzyl thioethers from benzyl halides using thiourea
作者:Kevin S. Eccles、Curtis J. Elcoate、Simon E. Lawrence、Anita R. Maguire
DOI:10.3998/ark.5550190.0011.921
日期:——
A series of symmetrical and unsymmetricalbenzylthioethers have been synthesised using a onepot reaction frombenzylhalides and thiourea. This procedure avoids the isolation or handling of malodorous thiols and generates high yields of benzylthioethers in excellent purity.