Microwave-assisted synthesis of quinoline alkaloids: 4-Methoxy-1-methyl-2-quinolinone and its analogs

Abstract

The microwave-induced synthesis of some quinoline alkaloids of the type 4-methoxy-1-methyl- 2-quinolinone including folimine is reported. The precursors 4-hydroxy-2-quinolinone derivatives were effectively prepared in a single step from aniline and diethylmalonate using p- toluenesulfonic acid as a catalyst and these intermediates were converted to the titled quinoline alkaloids by treatment with dimethyl sulfate, N,N-dimethylformamide and potassium carbonate. The presented synthentic procedure is a convenient, simple and fast alternative for synthesizing 4-methoxy-1-methyl-2-quinolinone and its derivatives.