syn-Selective asymmetric cross-aldol reactions between aldehydes and glyoxylic acid derivatives catalyzed by an axially chiral amino sulfonamide.

syn-Selective asymmetric cross-aldol reactions of aldehydes with tert-butyl glyoxylate and glyoxamide were realized by the use of an axially chiral amino sulfonamide (S)-1. The cross-aldol products obtained are densely functionalized and readily converted to synthetically useful and important chiral building blocks such as γ-lactone and γ-lactam.