Palladium-catalyzed multiple arylation of phenyl ketones with aryl bromides

Benzyl phenyl ketones undergo triarylation upon treatment with excess aryl bromides in the presence of a catalytic amount of ce:simple-parad(PPh3)4 and Cs2CO3 as base in o-xylene on the α- and two ortho-positions of the carbonyl group to give diphenymethyl 2,6-diphenylphenyl ketone derivatives as the predominant products. Acetophenone and diphenylmethyl phenyl ketone similarly undergo tetra- and diarylations, respectively.