原位产生的3-羟基-2,4,6-吡啶三酸配位的Cu(Ⅱ)配合物的合成及配体反应机理分析

摘要

以2,4,6-三甲基吡啶(2,4,6-tmpy)和Cu(NO3)2为原料,采用水热法原位合成一个新的含3-羟基-2,4,6-吡啶三酸根(2,4,6-opyt3-的Cu(Ⅱ)配合物[Cu2(2,4 ,6-opyta)(H2O)2]·2H2O,并对其进行了红外、元素分析和X-射线单晶衍射测定.单晶结构分析表明,该配合物中Cu1,Cu2均采取五配位的四方锥几何构型,[Cu4(2,4 ,6-opyta)2(H2O)4]结构基元间通过Cul-O5配位作用连成波浪形的层状结构.结晶水、配位水及羧基氧之间存在丰富的氢键作用进一步将二维层拓展成三维超分子网络.新产生的配体2 ,4,6-opyta3-是由Cu(Ⅱ)诱导HNO3氧化2 ,4 ,6-tmpy发生氧化和羟基化反应原位合成的.%A new Cu(Ⅱ) Complex [Cu2(2,4,6-opyta)(H2O)2]·2H2O was prepared hydrothermally through 2,4,6-trimethylpyridine (2,4,6-tmpy) and Cu (NO)2, where 2,4,6-opyta3- is 3-hydroxy-2,4,6-pyridinetricarboxylate. X-ray analysis indicates that Cut and Cut centers in this complex both adopt a five-coordinated square-pyramidal geometry. Adjacent [Cu4(2,4,6-opyta)2(H2O)4] units link each other through Cul-05 coordination interaction and form a wave-like 2D layer. These 2D layers further form a 3D supermolecular network through abundant intra-,intermolecular hydrogen-bonding interactions between water molecules and carboxylate oxygen atoms. Furthermore,the new ligand 2,4,6-opyta3- is derived from copper-mediated oxidation and hydroxylation of 2,4,6-tmpy by utilizing nn, b=0.67153(7) nn, c=1.715 29(18) nm, β=107.109(2)°, V=1.235 4(2) nm3, Z=4, R,=0.0391, WR2=0.0980 (I2σ(I)). CCDC: 783944.