Platinum(II)-Catalyzed Ethylene Hydrophenylation: Switching Selectivity between Alkyl- and Vinylbenzene Production

The series of PtII complexes [(xbpy)­Pt­(Ph)­(THF)]­[BAr′4] (xbpy =4,4′-X-2,2′-bipyridyl, X = OMe, tBu, H, Br, CO2Et, NO2; Ar′ = 3,5-bis­(trifluoromethyl)­phenyl) are catalyst precursors for ethylene hydrophenylation. The bipyridyl substituent provides a tunable switch for catalyst selectivity that also has significant influence on catalyst activity and longevity. Less electron donating 4,4′-substituents increase the propensity toward styrene formation over ethylbenzene.