Heterocyclic compounds. Part XX. The kostanecki acylation of quinacetophenone, quinbenzophenone and γ-orcacetophenone, and synthesis of 6-hydroxy and 5-hydroxy chromones and coumarins

Abstract

The propionylation as well as butyrylation of quinacetophenone gave a mixture of chromones and coumarins, while its acetylation gave only the chromone. Similarly the acetylation of quinbenzophenone gave the coumarin. Thus coumarins which cannot be obtained by the Pechmann method can be readily prepared by this method. Similarly propionylation and butyrylation of γ-orcacetophenone gave the mixture of chromones and coumarins, while the benzoylation gave the flavone.