Some mono- and binuclear platinacyclopentane complexes: A comparative kinetic study of reaction of ethyl iodide with platina(II)cyclopentane and dimethylplatinum(II) complexes

Abstract

The reaction of Li(CH2)4Li with [PtCl2(SEt2)2] yielded an unstable complex, probably [{Pt(CH2CH2CH2CH2)(μ-SEt 2)}2], 1. Complex 1 reacts with bis(diphenylphosphino)methane, dppm, and forms [{Pt(CH2CH2CH2CH2)(μ-dppm)} 2], 2. Complex 2 has been fully characterized using multinuclear NMR and FAB mass spectroscopies and shown to be fluxional in solution. The bright red platinacyclopentane complex [Pt(CH2CH2CH2CH2)(bpy)], 3, in which bpy=2,2′ bipyridyl, has been prepared by reaction of 1 with bpy. In a comparative kinetic study, it was demonstrated that at different temperatures, EtI reacted 2.2-2.6 times faster with the platina(II)cyclopentane complex 3 than with the dimethyl analogue [PtMe2(bpy)].