Between MOFs and molecules: organolead(IV) compounds with chain structures.

Organolead compounds are of interest mainly as catalysts and organolead halides have proved to be very efficient materials for solar cells. Two organolead(IV) dimethylarsinates, namely catena-poly[[triphenyllead(IV)]-μ-chlorido-[triphenyllead(IV)]-μ-dimethylarsinato-κ2O:O'], [Pb2(C6H5)6(C2H6AsO2)Cl]n or [(Ph3Pb)2Cl(O2AsMe2)], (1), and poly[chlorido(μ3-dimethylarsinato-κ3O:O,O':O')diphenyllead(IV)], [Pb(C6H5)2(C2H6AsO2)Cl]n or [(Ph2ClPb)(O2AsMe2)], (2), together with the triphenyllead(IV) diphenylphosphinate catena-poly[[triphenyllead(IV)]-μ-diphenylphosphinato-κ2O:O'], [Pb(C6H5)3(C12H10O2P)]n or [(Ph3Pb)(O2PPh2)], (3), have been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and mass spectrometry. In (1), a chain structure was found with alternating chloride and Pb-O-As-O-Pb arsinate bridges between five-coordinate PbIV atoms. In (2), bidentate and chelate-like bonded dimethylarsinate ligands form double chains with heptacoordinated PbIV atoms. In (3), a pentacoordinated PbIV atom is connected by Pb-O-P-O-Pb phosphinate bridges to form a linear chain. Obviously, the steric demand of the phenyl ligands at PbIV reduces the possibility of interconnections via polydentate ligands to one dimension only. Thus, no metal-organic frameworks (MOF) are formed but instead various chain structures are observed.