Enantioselective copper-aminopyridine-catalyzed aza-Henry reaction with chelating N-(2-pyridyl)sulfonyl imines

ABSTRACT This article describes a copper‐catalyzed aza‐Henry reaction. Copper complexes of camphor‐derived aminopyridines catalyze the addition of nitromethane to N‐(2‐pyridyl)sulfonyl aldimines to give the corresponding β‐nitrosulfonamides with good yields and variable enantiomeric excesses (up to 83%). An example of transformation of these compounds into N‐(2‐pyridyl)sulfonyl‐α‐amino acids and deprotection of the sulfonamide with Mg–MeOH is provided. Chirality 24:441–450, 2012. © 2012 Wiley Periodicals, Inc.