Synthesis and characterization of a new nonanuclear Ni(<scp>ii</scp>) cluster from a pyridyl-alcohol ligand
作者:Alexandre Massard、Guillaume Rogez、Pierre Braunstein
DOI:10.1039/c3dt52744a
日期:——
The reaction of one equivalent of 2-methyl-1-(pyridin-2-yl)propan-2-ol (HL) with two equivalents of [Ni(OAc)2·4H2O] in methanol afforded the nonanuclear coordination cluster [Ni9(HL-κ2N,O)4(OAc-κ2O)2(μ2-OAc-κ1O)2(μ2-OAc-κ2O,O′)4(μ3-OAc-κ2O;κ2O,O′)2(μ3-OMe)8] (1). All nickel ions are hexacoordinated and show a slightly distorted octahedral coordination geometry. This unusual centrosymmetric coordination cluster can be described as constituted by two cubane moieties connected by a linker comprising a nickel atom, situated on the inversion centre, four bridging acetates and two triply-bridging acetates. Each cubane contains four Ni(II) centres and four triply-bridging methoxide anions, two of the Ni(II) centres are N,O-chelated by the ligand HL, another Ni(II) is chelated by an acetate ligand and the fourth Ni(II) centre is connected to the exo-cubane Ni(II) through three acetate ligands which each have a different bonding mode: μ2-κ2O,O′, μ2-κ1O, and μ3-κ1O;κ2O,O′. The magnetic and catalytic properties for ethylene oligomerization of the unusual complex 1 have been investigated.
将一个当量的2-甲基-1-(吡啶-2-基)丙醇(HL)与两个当量的[Ni(OAc)2·4H2O]在甲醇中反应,得到了非核协调簇[Ni9(HL-κ2N,O)4(OAc-κ2O)2(μ2-OAc-κ1O)2(μ2-OAc-κ2O,O′)4(μ3-OAc-κ2O;κ2O,O′)2(μ3-OMe)8](1)。所有镍离子均为六配位,呈现出略微扭曲的八面体配位几何。这个不寻常的中心对称协调簇可以描述为由两个立方烷单元通过一个包含一个镍原子的连接体连接,该镍原子位于反转中心,配有四个桥联醋酸根和两个三桥联醋酸根。每个立方烷单元包含四个Ni(II)中心和四个三桥联的甲氧基阴离子,其中两个Ni(II)中心由配体HL进行了N,O配位,另一个Ni(II)中心由一个醋酸配体进行了配位,而第四个Ni(II)中心则通过三种不同配位方式的醋酸配体与外立方烷Ni(II)相连:μ2-κ2O,O′、μ2-κ1O和μ3-κ1O;κ2O,O′。对于这一不寻常复合物1的磁性和催化性质在乙烯的聚合方面进行了研究。