Pseudo six-component stereoselective synthesis of 2,4,6-triaryl-3,3,5,5-tetracyanopiperidines

Abstract

The Knovenagel–Michael–Mannich cascade reaction of aromatic aldehyde (3 equiv.), malononitrile (2 equiv.) and ammonium acetate or aqueous ammonia provides convenient stereoselective access to cis,cis-2,4,6-triaryl-3,3,5,5-tetracyanopiperidines in 62–94% yields. Six new bonds form as a result of the domino process, ammonium acetate serving as a nitrogen source.