Alkylation and acylation reactions. Part II. The interaction of aryloxyacetyl chlorides with aluminium chloride

Abstract

The interaction of substituted aryloxyacetyl chlorides with aluminium chloride in benzene leads to intramolecular and intermolecular acylation and diphenylmethane, the corresponding phenol, and an o-benzylphenol, the product ratio varying with the substituent. The alkylation products arise from unimolecular decarbonylation of the aryloxyacetylium ion, followed by attack on the solvent, and cleavage of the benzyl ether. Electron-releasing substituents assist decarbonylation and cyclisation to the benzofuran-3(2H) one while electron-attracting substituents lead to a high proportion of the 2-aryloxyacetophenone.