Continuous Flow Telescoped Synthesis of Benzofurans Starting from Nitroalkanes and O-Acetyl Salicylaldehydes

Dedication

Dedicated to Professor Paul Knochel on the occasion of his 70th birthday.

Abstract

Herein, we report a new practical flow chemical synthesis of benzofurans starting from nitroalkanes and O-acetyl salicylaldehydes. The protocol involves two different sequential steps: (i) an initial base-promoted nitroaldol condensation, and (ii) a Nef reaction promoted by tin (II) chloride dihydrate. The target benzofurans are obtained in satisfactory overall yields.

Keywords

Flow chemistry - Benzofurans - Nitroalkanes - Cyclization - Heterocycles

Publication History

Received: 22 May 2025

Accepted after revision: 24 June 2025

Accepted Manuscript online:
24 June 2025

Article published online:
15 August 2025

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