Synthesis, Crystal Structures, and Thermolysis Studies of Heteronuclear Transition Metal Aluminum Alcoholates

Heteronuclear alcoholate complexes [M{Al(OiPr)(4)}(2)(bipy)] (2-M, M = Fe, Co, Ni, Cu, Zn) and [M{Al(OcHex)(4)}(2)(bipy)] (3-M, M = Fe, Co, Ni, Zn) are formed by adduct formation of [M{Al(OiPr)(4)}(2)] (1-M, M = Fe, Co, Ni, Cu, Zn) with 2,2'-bipyridine and transesterification reaction withcHexOAc. According to crystal structure analyses, in2-Mand3-Mthe central transition metal ion M(2+)is coordinated by two chelating Al(OR)(4)(-)moieties and one bipyridine ligand in an octahedral arrangement. Treating1-Cuwith 2,2'-bipyridine leads to a reduction process, whereat the intermediate [Cu{Al(OiPr)(4)}(bipy)(2)][Al(OiPr)(4)] (4) could be structurally characterized. During conversion of theiso-propanolate ligands in1-Cuto cyclohexanolate ligands, Cu(2+)is reduced to Cu(+)forming [Cu{Al(O (c) Hex)(4)}(py)(2)] (5). UV/Vis-spectra and results of thermolysis studies by TG/DTA-MS are reported.