Hemilability of P(X)N-type ligands (X = O, N–H): rollover cyclometalation and benzene C–H activation from (P(X)N)PtMe2 complexes

Abstract

The thermolyses of (^tBuP(O)N)PtMe₂ (1, ^tBuP(O)N = (di-tert-butylphosphinito)pyridine) and (^tBuP(N–H)N)PtMe₂ (3, ^tBuP(N–H)N = (di-tert-butylphosphino)-2-aminopyridine) in benzene-d₆ were investigated. With (^tBuP(O)N)PtMe₂, the product of a rollover cyclometalation of the pyridyl ring was observed in 80% yield along with formation of CH₄. In contrast, thermolysis of (^tBuP(N–H)N)PtMe₂ resulted in competing rollover cyclometalation and intermolecular benzene C–H activation with production of a mixture of CH₄ and CH₃D.