Short Synthesis of Pulchellalactam

Abstract

tert‐Butyl 4‐methyl‐2‐oxo‐2,5‐dihydro‐1H‐pyrrole‐1‐carboxylate 4 was synthesized by a short two‐step procedure: regioselective 1,3‐dipolar diazomethane cycloaddition to N‐Boc‐pyrrolinone 2 and thermolysis of the adduct. The compound 4 could be converted in one step into pulchellalactam.

Keywords:

• Diazomethane cycloaddition
• marine metabolite
• pyrazolines
• unsaturated γ‐lactams

Acknowledgment

We are grateful to CNRS and Professor J. Y. Lallemand, director of ICSN, for financial support (J.‐P. H; V. C.).