Disproportionation of PtPh(CH2COMe)(cod) and Conproportionation of PtPh2(cod) and Pt(CH2COMe)2(cod) via Intermolecular Phenyl Ligand Transfer

PtI(Ph)(cod) (cod = 1,5-cyclooctadiene)reacts with acetone in the presence of Ag 2 O to give a mixture of Pt(CH 2 COMe)(Ph)(cod) ( 1 ), PtPh 2 (cod) ( 2 ), and Pt(CH 2 COMe) 2 (cod) ( 3 ) in a molar ratio of 61:20:19. Complex 1, having the phenyl and acetonyl ligands, was isolated by recrystallization of the products and characterized by X-ray crystallography. The reaction of AgBF 4 with PtI(Ph)(cod) forms [PtPh(cod)(acetone- d 6 )]BF 4 and does not give a diarylplatinum complex. Thus, Ag 2 O, in the reaction of PtI(Ph)(cod) with acetone, promotes activation of both the Pt−I bond of PtI(Ph)(cod) and a C−H bond of acetone. Heating of 1 in acetone at 50 °C causes its partial disproportionation into 2 and 3 to give a mixture of the above three complexes. An equimolar mixture of 2 and 3 in acetone undergoes conproportionation into 1 at 50 °C to give a mixture of the complexes. The conproportionation is completed in 30 h to form the mixture with [ 1 ]:[ 2 ]:[ 3 ] = 66:17:17, while the above disproportionation of 1 does not attain equilibrium even after 70 h. The disproportionation and conproportionation of these complexes are observed also in benzene at 50 °C.