Lewis Base Catalyzed Enantioselective Aldol Addition of Acetaldehyde-Derived Silyl Enol Ether to Aldehydes

Abstract

Chiral phosphoramide catalyzed-enantioselective aldol addition of an acetaldehyde-derived trialkylsilyl enol ether to aromatic aldehydes provides protected aldol products in good yields with good to excellent enantioselectivities. Preliminary studies show that the aldolization intermediate (a chlorohydrin adduct) can be trapped with tert-butyl isocyanide to form an α-hydroxy lactone with good selectivity in a single-pot operation.