Synthesis of functionalized flavones from 3-halo-2-(methylthio)-4H-chromen-4-ones

A simple and efficient method for the synthesis of flavones was achieved by selective sulfide Liebeskind-Srogl cross-coupling reaction of 2-(methylthio)-4H-chromen-4-ones and 3-halo-2-(methylthio)-4H-chromen-4-ones with arylboronic acids. This method is the first example of employing Liebeskind-Srogl coupling for the synthesis of flavones. Various aryl groups can be directly installed to the chromone ring. The structure of all the synthesized compounds were assigned by spectroscopic analysis.