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合成了链酚胺型 N3O配体 N-(2-羟基苄基 )-二乙烯三胺 (HL),用元素分析 ,IR和 1H NMR等手段进行了表征。用 pH电位滴定法，在 25± 0.1℃ ,I=0.10(KNO3)条件下，研究了该配体质子化及其与 Zn?离子配位热力学。在 25± 0.1℃ ,I =0.10(KNO3)， pH =7～ 9(50mmol· L－ 1缓冲溶液 )范围内，通过分光光度法测定了配合物催化对硝基苯酚乙酸酯 (NA)水解动力学，得到了 NA催化水解二级反应速率常数 kc。结果表明： Zn?离子与配体的氨基和酚羟基配位之后，还与一个水分子配位。配位酚羟基和水分子的离解常数 pKa值分别为 5.22和 9.47。在中性 pH值可以产生亲核试剂 Zn?…－ OH，对 NA水解有较好的催化效果， pH=9.0时， kc=3.2× 10－ 2mol－ 1· L－ 1· s－ 1。
The N - (3 - hydroxybenzyl) - diethylenetriamine (HL), an N3O ligand, was synthesized and characterized by means of elemental analysis, IR and 1H NMR. The protonation of the ligand and the thermodynamics of its coordination with Zn (superscript 2+) were investigated by pH potentiometric titration at 25 ± 0.1 ℃ and I = 0.10 (KNO3). The catalytic activity of the complex to nitrophenol acetate (NA) was determined spectrophotometrically at 25 ± 0.1 ℃ in the range of I = 0.10 (KNO3) and pH = 7-9 (50 mmol · L-1 buffer) Hydrolysis kinetics, obtained by the NA catalytic hydrolysis of the second reaction rate constant kc. The results show that Zn ¢ ó ions coordinate with the ligands amino groups and phenolic hydroxyl groups and coordinate with a water molecule. The dissociation constants pKa of the coordination phenolic hydroxyl and water molecules were 5.22 and 9.47, respectively. At neutral pH, nucleophilic Zn (OH) - OH can be produced, which has a good catalytic effect on NA hydrolysis. At pH = 9.0, kc = 3.2 × 10-2mol -1 · L -1 · s -1.