Synthesis of N-Vinyl Nitrones via 1,4-Conjugate Elimination

Abstract

A number of structurally and electronically diverse N-vinyl nitrones have been synthesized by a two-step method. The sequence consists of condensation of an α-chloroaldehyde or an α-phenoxy- or α-acetoxy ketone with a substituted benzyl hydroxylamine to provide the corresponding nitrone. Treatment of these species with a base induces a 1,4-elimination to provide the desired N-vinyl nitrone in good to excellent yields.