Olefin Hydroarylation Catalyzed by (pyridyl-indolate)Pt(II) Complexes: Catalytic Efficiencies and Mechanistic Aspects

A series of Pt­(II) complexes of the type (N–N)­PtPh­(SR₂) (N–N = 2,2′-pyridyl-indolate) were prepared, and their performance as catalysts for the hydroarylation of olefins was assessed. Evidence that the catalysis is homogeneous and is Pt-mediated is provided by control experiments with added hindered base (2,6-di-<i>tert</i>-butyl-4-methylpyridine) and Hg(0). Two potential catalytic intermediates, (^<i>t</i>BuPyInd)­PtPh­(C₂H₄) and (^<i>t</i>BuPyInd)­Pt­(CH₂CH₂Ph)­(C₂H₄), were synthesized, and their catalytic efficacy was explored. Additionally, decomposition and deactivation pathways, including styrene formation via β-hydride elimination and ligand reductive demetalation, were identified