Competitive Trapping of Equilibrating Pt(IV) Hydridoalkyl and Pt(II) Alkane Complexes: A Valuable Tool for the Mechanistic Investigation of C?H Activation Reactions

Rapid equilibria between M(a-hydrocarbon) and M(H)(hydrocarbyl) species is a distinct feature of C-H activation reactions at transition-metal complexes of great structural diversity. In this contribution, we summarize recent work that has been done in order to better understand intimate details about important steps in C-H activation reactions at cationic Pt diimine complexes. An experimental design involving competitive trapping of the rapidly interconverting intermediates is utilized. The results provide new information about the processes by which hydrocarbons enter the coordination sphere of Pt, and about the kinetically preferred site of protonation of (diimine)Pt(CH 3 ) 2 complexes.