Direct Synthesis of 4-Acetyl-1-alkyl-1H-pyrrol-2(5H)-ones from Difunctionalized Allyl Bromide

Abstract

We describe a simple and efficient protocol for accessing some unsaturated heterocyclic compounds in a direct evaluation of allyl bromide as Z-ethyl 3-bromomethyl-4-oxopent-2-enoate. The latter reacts with primary amines via two successive nucleophilic substitutions followed by a 5-exo-trig cyclization to produce selectively 4-acetyl-1-alkyl-1H-pyrrol-2(5H)-ones in good yields.

GRAPHICAL ABSTRACT

Keywords:

• 5-Exo-trig cyclization
• primary amines
• pyrrol-2(5H)-ones
• Z-ethyl 3-bromomethyl-4-oxopent-2-enoate

Notes

^a Isolated yield after purification by column chromatography.