四苯基[b,f,j,n][1,5,9,13]四氮杂环十六碳炔镍轴向氮碱加合物的合成、结构和性质研究

Synthesis, Crystal Structure and Properties of TAAB Nickel Adducts with Axial N-Base Ligands

合成了3个四苯基[b,f,j,n][1,5,9,13]四氮杂环十六碳炔镍轴向氮碱加合物[Ni(TAAB)(L)_2](BF_4)_2(L为吡啶、咪唑、DMF)以及4,4′-联吡啶桥联配合物[Ni(TAAB)(μ-4,4′-bipy)]。[(ClO_4)_2·H_2O]_((??))。用元素分析、IR和热分析对标题化合物作了表征。双吡啶加合物的晶体结构显示,TAAB大环呈马鞍形结构,轴向配位的吡啶环平面相互垂直,轴向的2个Ni—N键长明显比赤道平面的4个Ni—N键长大,形成拉长的配位八面体。4,4′-联吡啶配合物的变温磁化率表明,镍(Ⅱ)离子间存在反铁磁性磁交换相互作用。

Four adducts of Py, Im, DMF and 4,4'-bipy with Ni(TAAB)2+ , where TAAB = tetraben-zo[b,f,j,R][1,5,9, 13]tetraazacyclohexadecine, were synthesized and characterized by elementary analysis, IR and thermal analysis. The crystal structure of [Ni(TAAB)(Py)2](BF4)2has been determined. The crystal belongs to a monoclinic system with space group P21/n, α=1. 6465(6) nm, b= 1.2486(5) nm, c= 2.0219(1) nm,β=113.79°, V=3. 8039 nm3, Z=4, R= 0.068. TAAB macrocyclic ligand presents a decidedly saddle-shaped appearance. The planes of two pyridine molecules are perpendicular to each other. The bond distances of Ni-N(n)(n= 10,20,30,40) are in the range of 0. 1983-0. 2043 nm while the bond distances of Ni-N(B)(n=5,6) are 0. 2182-0. 2189 nm, forming a distorted octahedron coordination geometry around nickel ion. The variable-temperature magnetic susceptibility of 4,4'-bipyridine-bridging nickel TAAB complex obeys the Curi-er-Weiss law (θ= - 44 K) and indicates an antiferromagnetic exchange interaction between nickel ions.