Trifluoroacetylation of 2-Methyl- and 2-Ethylchromones: A Convenient Access to 2-Trifluoroacetonyl Chromones

摘要

A simple and efficient method for the synthesis of 2-(3,3,3- trifluoroacetonyl) chromones and isoflavones has been devel- oped. This method involves an initial in situ generation of the vinyl ethers from 2-methyl- or 2-ethylchromones/isoflavones and their subsequent acylation with trifluoroacetic anhydride in the presence of CF3COOK. This pathway provides convenient access to novel fluorinated analogs of naturally occurring chromones.