Synthesis of 2-Aroyloxyacetophenones as Intermediates for Flavone Synthesis

Flavone의 합성 중간체인 2-Aroyloxyacetophenone류의 새로운 합성법

We have synthesized some 2-(2-benzyloxybenzoyloxy)-and 2-(2,6-dibenzyloxybenzoyloxy)-acetophenones as intermediates for flavone synthesis. The reaction of polyoxygenated 2-hydroxyacetophenones with 2-benzyloxybenzoic acid or 2,6-dibenzyloxybenzoic acid in the presence of dicyclohexylcarbodiimide and p-dimethylaminopyridine resulted in a good yield$(70{\sim}89%)$ of 2-(2-benzyloxybenzoyloxy)-acetophenones or 2-(2,6-dibenzyloxybenzoyloxy) acetophenones under milder conditions and in shorter time than the previous methods. This new methods using benzoic acids instead of benzoyl chlorides saves one reaction step of acid chlorination in comparision of the previous methods.