Rhodium-catalyzed synthesis of 2,3-diaryl-1,4-diketones via oxidative coupling of benzyl ketones using α-thioketone oxidizing reagent

RhH(PPh3)4 and 1,2-bis(diphenylphosphino)benzene (dppBz) catalyzed the oxidative coupling reaction of aryl benzyl ketones giving 2,3-diaryl-1,4-diketones in high yields. 3,3-Dimethyl-1-methylthio-2-butanone was used as the oxidizing reagent, which was converted to 3,3-dimethyl-2-butanone and dimethyl disulfide. Rhodium enolates were catalytically formed from ketones, which underwent oxidative coupling using an organosulfur reagent.