Sc(III)-catalyzed enantioselective addition of thiols to α,β-unsaturated ketones in neutral water

Org Lett. 2011 May 6;13(9):2150-2. doi: 10.1021/ol200379r. Epub 2011 Apr 1.

Abstract

This report concerns Lewis acid catalyzed enantioselective sulfa-Michael addition in neutral water by using a very efficient Sc(OTf)(3)/bipyridine 1 catalytic system. It is noteworthy that the protocol presented employs water as a reaction medium and allows us to obtain very high stereoselectivity and satisfactory yields for β-keto sulphides deriving from aliphatic thiols. The recovery and reuse of both the aqueous medium and the catalytic system is also reported.