Process for the preparation of ethynylbenzaldehydes

摘要

A multi-step process for the preparation of ethynylbenzaldehydes from bromo- or iodobenzaldehydes is disclosed. The arylhalogen is replaced with a protected ethynyl compound which is subsequently cleaved by base to form the arylacetylene. The aldehydic functionlity is preserved by formation of a corresponding Schiff's base or acetal, and its subsequent regeneration by treatment with aqueous acid.