Synthesis and characterization of new homo-heterobinuclear platinum(II) complexes with dimethylphosphonate as bridging ligands. Crystal structure of [( η2dppm)Pt{ μ-P(O)(OMe) 2} 2 ( μ-I)PtMe 3

Abstract

The preparation of the new neutral complex [( η 2dppm)Pt(P(O)(OMe) 2) 2] ( 1) (dppm  1,1-bis(diphenylphosphino) methane) and its behaviour as a chelate (O,O)-donor ligand is described. This ligand reacts with [Me 3PtI] 4 to give the homobimetallic complex [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2( μ-I)PtMe 3] ( 2), which in turn reacts with AgPF 6 in the presence of PPh 3 to yield the new cationic complex [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2}PtMe 3(PPh 3)}]PF 6 ( 3). In contrast, the treatment of binuclear complexes [{Pd(μ-Cl)(2-MeC 3H 4)} 2] and [{Rh(μ-Cl)(cod)} 2] with silver perchlorate in the presence of the bidentate ligand 1 yields the heterobinuclear compounds [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2Pd( η 3MeC 3H 4)]ClO 4 ( 4) and [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2Rh(cod)]ClO 4 ( 5). Complex 5 reacts with an atmosphere of CO at room temperature yielding the cis-dicarbonyl complex [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2Rh(CO) 2]ClO 4 ( 6). The structure of complex [( η 2dppm)Pt{ μ-P(O)(OMe) 2} 2( μ-I)PtMe 3] has been determined by single crystal X-ray diffraction methods.