基于2-氨基-3-羟基-吡啶Schiff碱的双核Ni(Ⅱ)和Zn(Ⅱ)配合物:合成、超分子结构和光谱性质

摘要

Two 2-amino-3-hydroxy-pyridine Schiff base binuclear Ni(Ⅱ) and Zn(Ⅱ) complexes,[Ni(L1)(DMF)]2 (1) (H2L1=4-hydroxy-3-((3-hydroxy-pyridin-2-ylimino)-methyl)-chromen-2-one) and [Zn (L2) (H2O)]2· 2DMF (2) (H2L2=2-((3,5-dibromo-2-hydroxy-benzylidene)-amino)-pyridin-3-ol) have been synthesized and characterized by elemental analyses,IR,UV-Vis,emission spectra and X-ray crystallography.X-ray crystallography analyses showed that complexes 1 and 2 all possess the binuclear structures,consisting of two metal ions,two ligand units and two coordinated solvent molecules,in which the difference is that complex 2 contains two solvent molecules.Complexes 1 and 2 crystallize in the monoclinic space group P21/c and the center Ni(Ⅱ) and Zn(Ⅱ) are all fivecoordinated slightly distorted square pyramid geometry by four O atoms and one imine N atoms.Complex 1 (or 2) links some other molecules into an infinite 3D network supramolecular structure via intermolecular hydrogen bond,C-H… π or π… π stacking interactions.And the fluorescent properties of H2L1,H2L2 and their corresponding Ni(Ⅱ) and Zn(Ⅱ) complexes have been discussed.The ligands H2L1 and H2L2 exhibit blue emission with the maximum emission wavelength λem=457 and 473 nm,and complexes 1 and 2 show green emission with λem=543 and 538 nm.CCDC:1855900,1;1855901,2.%合成了2个2-氨基-3-羟基-吡啶Schiff碱双核Ni(Ⅱ)和Zn(Ⅱ)配合物,[Ni(L1)(DMD]2(1)(H2L1=4-羟基-3-((3-羟基-吡啶-2-亚氨基))-苯并吡喃-2-酮)和[Zn(L2)(H2O)]2·2DMF(2)(H2L2=2-((3,5-二溴-2-羟基)-氨基)-吡啶-3-醇),并通过元素分析、红外光谱、紫外-可见吸收光谱、荧光光谱及X射线单晶衍射分析等手段进行了表征.X射线单晶衍射分析结果表明:配合物1和2均具有双核结构,均由2个金属离子和2个配体单元以及2个配位的溶剂分子组成,不同的是配合物2含有2个溶剂分子.配合物1和2都是单斜晶系、P21/c空间群,且中心金属Ni(Ⅱ)和Zn(Ⅱ)离子的空间构型均为五配位的扭曲的四方锥.此外,配合物1和2通过分子间氢键、C-H…π及π…π作用形成3D超分子结构.此外,讨论了H2L1,H2L2及其相应的Ni(Ⅱ)和Zn(Ⅱ)配合物的荧光性质.配体H2L1和H2L2呈现蓝色发射,最大发射波长λem分别为457和473 nm,而配合物1和2显示绿色发射,λem分别为543和538 nm.