Catalytic Asymmetric Thiofunctionalization of Unactivated Alkenes
摘要:
Catalytic asymmetric sulfenylation of double bonds has been achieved using a BINAM-based phosphoramide catalyst and an electrophilic sulfur source. Simple alkenes as well as styrenes afforded sulfenylated tetrahydrofurans and tetrahydropyrans by closure with pendant hydroxyl or carboxyl groups. Intermolecular thiofunctionalizations were also achieved with simple alcohols or carboxylic acids as the nucleophiles.
Enantioselective oxysulfenylation and oxyselenenylation of olefins catalyzed by chiral Brønsted acids
作者:Huan Guan、Haining Wang、Deshun Huang、Yian Shi
DOI:10.1016/j.tet.2012.01.006
日期:2012.3
This paper describes Brønsted acid catalyzed enantioselective oxysulfenylation and oxyselenenylation of olefins. Enantiomerically enriched tetrahydrofurans are formed with up to 63% ee with dibenzoyl-d-tartaric acid and its derivatives as catalyst. Chiral β-carboxyl sulfides and selenides have also been obtained with up to 50% and 84% ee, respectively, via enantioselective desymmetrization of thiiranium