ETA(3)-TRIMETHYLENEMETHANE COMPLEX OF PLATINUM

The first trimethylenemethane complex of platinum, (PPh(3))(2)Pt(eta(3 )-CH2C(C(CO(2)Me)(2))CHPh) (1), was synthesized from [(PPh(3))(2)Pt(et a(3)-CH(2)CCPh)]O3SCF3 and Na[CH(CO(2)Me)(2)]. Its structure shows eta (3) bonding of the trimethylenemethane ligand to platinum, with a fold angle of 59.9 degrees between the planes C-Pt-C and coordinated C-C-C . 1 undergoes protonation at the C(CO(2)Me)(2) methylene carbon atom t o yield (PPh(3))(2)Pt(eta(3)-CH2C(CH(CO(2)Me)(2))CHPh)](+) and [3 + 2] cycloaddition of tetracyanoethylene to the organic ligand to afford a platinum-olefin complex, (3))(2)Pt(PhCH=CCH2C(CN)(2)C(CN)(2)C(CO(2)Me )(2)).