in dichloromethane Kinetics; (CH3)4Sn is added to a stirred soln. of (MCOT)PtBr2, soln. is stirred for 2 h.; Solvent is evapd., residue is washed with hexane to remove (CH3)3SnBr, elem. anal., isolated yield of dimeric compound 26percent (ratio trans:cis=3.3:1).;