title: Promoting C-C Bond Coupling of Benzyne and Methyl Ligands in Electron-Deficient (triphos)Pt-CH3+Complexes.
abstract: In situ generated benzyne reacts at room temperature with (triphos)Pt-CH3+to form a five-coordinate π-complex (2) that is isolable and stable in solution. Thermolysis of2at 60 °C generates (triphos)Pt(o-tolyl)+(3), which is the product of formal migratory insertion of CH3-onto the coordinated benzyne. The reaction of2with the acid Ph2NH2+yields toluene at room temperature over the course of 8 h, while the same reaction with3only proceeds to 40% conversion over 2 days. These data indicate that the protonolysis of2does not proceed by CH3migration onto benzyne to form3followed by protodemetalation. Instead, the data suggest either that protonation of2is first and is followed by H migration to yield a PtIVPh(Me) dication or that this latter species is generated by direct protonolysis of coordinated benzyne prior to reductive elimination of toluene.
authors.affiliation: Department of Chemistry, College of Sciences, Shiraz University , Shiraz 71454, Iran.
authors.forename: Marzieh Dadkhah
authors.initials: MD
authors.lastname: Aseman
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Christina A
authors.initials: CA
authors.lastname: Roselli
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States.
authors.forename: Michel R
authors.initials: MR
authors.lastname: Gagné