Unexpected one-step synthesis of 3-benzoyl-2-phenylbenzofurans under Wittig conditions

Begala, Michela

Primo

;Caboni, Pierluigi

Secondo

;Matos, Maria João

Penultimo

;Delogu, Giovanna Lucia

Ultimo

2018-01-01

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Abstract

The reaction of 2-hydroxybenzyltriphenylphosphonium bromide with substituted benzoyl chlorides under Wittig conditions, led to 2-phenylbenzofuran derivatives 4a–p and the unexpected formation of 3-benzoyl-2-phenylbenzofuran derivatives 5a–p. Benzoyl chlorides possessing electron-withdrawing groups afforded 3-benzoyl-2-phenylbenzofuran derivatives in higher yields than those with electrondonating groups. This reaction represents a simple and regioselective, one-pot route towards the preparation of deactivated 3-benzoyl-2-phenylbenzofuran compounds which are difficult to obtain by the direct acylation of 2-phenylbenzofurans.