A PCN ligand system. Exclusive C-C activation with rhodium(I) and C-H activation with platinum(II)

Reaction of the new aromatic aminophosphine ligand 1-((diethylamino)methyl)-3-((di-tert-butylphosphino)methyl)-2,4,6-trimethylbenzene (4) with [Rh(COE)(2)Cl](2) (COE = cyclooctene) or with [Rh(ethylene)(2)Cl](2) at room temperature results in selective carbon-carbon bond activation, yielding the complex ClRh(CH3)[C6H(CH3)(2)(CH2N(C2H5)(2))(CH2P(t-Bu)(2))] (5). No competing C-H activation was observed during the course of the reaction. When 4 was reacted with (COD)PtCl2 (GOD = cyclooctadiene), selective C-H activation of the methyl group situated between the phosphine and amine groups took place, with concomitant intramolecular H transfer to the amine ligand, resulting in the zwitterionic Pt(II) complex Cl2PtCH2(C6H(CH3)(2)(CH2NH(C2H5)(2))(CH2P(t-Bu)(2))(11).