Compositional and Structural Variety of Diphenyllead(IV) Complexes Obtained by Reaction of Diphenyllead Dichloride with Thiosemicarbazones

The reactions of PbPh2Cl2 in methanol with acetophenone, salicylaldehyde, pyridine-2-carbaldehyde, 2-acetylpyridine, and 2-benzoylpyridine thiosemicarbazones (HATSC, HSTSC, HPyTSC, HAcPyTSC, and HBPyTSC, respectively) were explored. Despite the similarities among these ligands, the reactions afforded solids with very diverse compositions and structural characteristics, which were in most cases analyzed by X-ray diffractometry (as was the structure of the free ligand HBPyTSC). In the complexes [PbPh2CI2(HATSC)]2, [PbP22Cl2(HSTSC)2], [{PbPh2CI(HPyTSC)}2][PbPh2Cl3(MeOH)]2, and [PbPh2CI(PyTSC)] the metal atoms are surrounded by more or less distorted octahedral coordination polyhedra; if both strong and weak interactions are considered, the lead atom in [PbPh2CI(AcPyTSC)] has coordination number 7 and distorted pentagonal bipyramidal coordination geometry, while [{PbPh2(BPyTSC)}2(PbPh2Cl4)]-2MeOH contains two different types of lead atom, one with octahedral and the other with pentagonal bipyramidal coordination. The complexes (H2AcPyTSC)[PbPh2Cl3] and [PbPh2CI(HAcPyTSC)][PbPh2cL3], which were also isolated, could not be crystallized. All these complexes are soluble in DMSO, and the compositions of these solutions were investigated using conductivity measurements and 1H and 207Pb NMR spectroscopy.