Sulfa-Michael reactions electrophiles

Although there are two distinctive approaches to enan-tioselective sulfa-Michael reactions—nucleophilic activation of thiols and electrophilic activation of alkenes—the recent emergence of bifunctional catalysts has greatly improved our understanding in the wider perspective of origin of asymmetric induction. A comprehensive review of asymmetric sulfa-Michael reactions by Ender and co-work-ers appeared in 2007 that covered the advances in this field from 1970s to 2005. " The reader is advised to refer this review article for a historical overview. The goal of this section, thus, is to focus on a few selected stereoselectivity issues in the asymmetric sulfa-Michael reactions and to document new advances made from 2005 to the present time. 

Scheme 7.48 Intermolecular sulfa-Michael/electrophilic amination reaction catalyzed by 31c.

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