Preparation by reaction of chromium trioxide with 5,6-dimethyl-2,3-diphenylbenzofuran or 5,6-di-methyl-2-(4-methylphenyl)- 3-phenylbenzofuran in acetic acid, followed by saponification of the keto ester so formed (2-benzoyloxy-4,5-dimethylbenzophenone).
