摘要 : The further use of di-2-pyridyl ketone [(2-PY)(2)CO] in nickel((II)) acetate chemistry has been investigated. Various synthetic procedures have led to the synthesis of complexes [Ni-4(O2CMe)(2){(2-py)(2)C(OH)O}(4)(H2O)(2)](ClO4)(2... 展开 The further use of di-2-pyridyl ketone [(2-PY)(2)CO] in nickel((II)) acetate chemistry has been investigated. Various synthetic procedures have led to the synthesis of complexes [Ni-4(O2CMe)(2){(2-py)(2)C(OH)O}(4)(H2O)(2)](ClO4)(2) (1), [Ni(O2CMe){(2-py)(2)C(OH)(2)}{(2-py)(2)CO}](ClO4)center dot H2O (2 center dot H20), [Ni-4(O2CMe)(3){(2-py)(2)C(OH)O}(4)](ClO4)center dot 2H(2)O center dot 2EtOH (3 center dot 2H(2)O center dot 2EtOH), [Ni-4(O2CMe)(4){(2-py)(2)C(OH)O}(4)]center dot 2MeCN (4 center dot 2MeCN), and [Ni-4(O2CMe)(3){(2-py)(2)C(OH)O}(4)](O2CMe)center dot 6H(2)O center dot MeCN (5 center dot 6H(2)O-MeCN). The Ni-II-mediated hydrolysis of (2-py)(2)CO to give the coordinated molecule (2-PY)2C(OH)2 or the monoanion (2-py)(2)C(OH)O- involves nucleophilic attack by H20 on the carbonyl group. The Ni-II ion in 2 center dot H2O is coordinated by one monodentate acetate, one N,N',O-tridentate chelating (2-py)(2)C(OH)(2) molecule, and one N,N'-bidentate chelating (2-py)(2)CO ligand. The tetranuclear cluster cation of 1 has a cubane {Ni-4(mu(3)-OR)(4)}(4+) core with Ni-II ions and deprotonated oxygen atoms occupying alternate vertices. The [Ni-4(O2CMe)(3){(2-py)(2)C(OH)O)(4)](+) cations present in the complexes 3 center dot 2H(2)O center dot 2EtOH and 5 center dot 6H(2)O-MeCN have almost identical cubane structures that are different from the structure of the cation of 1. The four metal ions in the centrosymmetric molecules of 4 center dot 2MeCN are located at four vertices of a defect dicubane (with two missing vertices) and are bridged by six oxygen atoms. Characteristic IR bands are discussed in terms of the known structures of 1-5. The magnetic data for the Ni-II cubane 1 has been modeled with two J values, and shows that the coupling consists of two ferromagnetically coupled pairs that are antiferromagnetically coupled to give a diamagnetic ground state. The magnetic properties of 4 have been modeled with three J values, and reveal competing antiferromagnetic and ferromagnetic coupling between the four Ni-II ions. 收起