Oxidative Addition of Dimesitylphosphine to Platinum(0): P−H vs P−C Activation

Reaction of Pt(dppe)(trans-stilbene) ( 1 ) with dimesitylphosphine initially gives, in equilibrium with 1, PHMes 2, and trans-stilbene, the kinetic product of P−H activation, Pt(dppe)(PMes 2 )(H) ( 2, dppe = Ph 2 PCH 2 CH 2 PPh 2, Mes = 2,4,6-Me 3 C 6 H 2 ). Further reaction of this mixture gives the thermodynamic product of P−C activation, Pt(dppe)(PHMes)(Mes) ( 3 ), plus the disproportionation products Pt(dppe) 2 ( 4 ) and Pt(0).