Bi- and Mononuclear Nickel(II) Trimethylacetate Complexes with Pyridine Bases as Ligands

Reaction of the nine-nuclear cluster Ni9(HOOCCMe3)4(μ4-ΟΗ)3(μ3-OH)3 (OOCCMe3)12 (1) with pyridine results in the binuclear species Py4Ni2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (2). Thermolysis of 2 at 100−140 °C in toluene or xylene leads to complex Py2Ni2(HOOCCMe3)2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (3). This complex can be converted back in 2 by the reaction of 3 with 2 equiv of pyridine. Thermolysis of solid 3 in vacuo at 170 °C gives the binuclear tetra-bridged trimethylacetate Py2Ni2(μ-OOCCMe3)4 (4) which can be reverted in 3 by reaction with 1 equiv of H2O and 2 equiv of HOOCCMe3. Compound 4 might be also prepared by the reaction of the complexs L2Ni2(μ-OOCCMe3)4 (L = 2,3-lutidine (5), Et3N (6)) with pyridine at 40−80 °C in hexane or benzene solution. Complexes 5 and 6 are formed in an one-step reaction by interaction of complex 1 and ligand L. Complex Dipy2Ni2(OOCCMe3)2(μ-OOCCMe3)2(μ-OH2) (7), an isoelectronic analogue of complex 2, was prepared by reacting 1 with Dipy. Thermolysis of solid 7 at 170 °C in vacuo ...