Bifunctional Thiourea-Catalyzed Stereoablative Retro-Sulfa-Michael Reaction: Concise and Diastereoselective Access to Chiral 2,4-Diarylthietanes

Dedicated to Professor Dieter Enders on the occasion of his 70^th birthday

Abstract

Owing to the chiral recognition capacity of bifunctional thioureas, a stereoablative retro-sulfa-Michael reaction has been developed. Utilization of a biphasic system enabled us to render the process catalytic. The usefulness of this methodology was further illustrated by the diastereoselective synthesis of all possible stereoisomers of 2,4-di­arylthiethanes.

Key words

organocatalysis - bifunctional - thiourea - stereoablative - sulfa-Michael

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