HETEROCOUPLING PROCESS FOR THE SYNTHESIS OF OPTIONALLY SUBSTITUTED 3- PHENYL-4H-CHROMEN-4-ONE

摘要

The invention provides novel process to prepare various substituted isoflavones using environment friendly approach. In this process, the reactions are done without solvents. The solventless reactions involve preparation of optionally substituted 3-bromo-4H-chromen- 4-one (3-halochromones) and heterocoupling of optionally substituted 3-bromo-4H-chromen-4-one with various bromo compounds in presence of zinc dust under basic conditions. The starting material optionally substituted 3-(Dimethylamino)-l-(2-hydroxyphenyl)- prop-2-en-l-one to prepare optionally substituted 3-bromo-4H-chromen-4-one is prepared by conventional methods.