Dedicated to Dr. Jacques Royer
An improved synthesis of unsaturated γ-lactams by condensation of various primary amines with 2,5-dimethoxy-2,5-dihydrofuran is described. A modified mechanism for this reaction is suggested. Synthesis of their N-α-methoxylated derivatives, as N-acyliminium ion precursors, is also reported. Finally, a short synthesis of (±)-crispine A is presented as an illustrative application.
Key words
unsaturated γ-lactams - aza-heterocycles -
N-acyliminium - 5-methoxypyrrolidin-2-one - crispine A