A Convenient Synthesis of N-Acylpyrroles from Primary Aromatic Amides

Abstract

Synthesis of N-acylpyrroles in 45-85% isolated yield from primary aromatic amides and excess 2,5-dimethoxytetrahydrofuran in presence of one equivalent of thionyl chloride is reported. This method has several advantages including short reaction times, mild reaction conditions, and easy workup. The technique works particularly well for deactivated aromatic amides.

Key words

N-acylpyrroles - primary amides - condensation - 2,5-dimethoxytertahydrofuran

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15

For example, benzamide in this reaction mixture (50-60 °C) formed N-benzoylindole and N-benzoylpyrrole after 5 h in 75% and 17% yield (GC), respectively.