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运用 ｐＨ电位滴定法，在 ２５±０．１℃ Ｔ， Ｉ＝０．１（ＫＮＯ_３）条件下，研究了 Ｃｕ（Ⅱ）与三吡啶胺（Ｌ’）和队（２’－羟基苄基）－二乙二胺（ＨＬ~２）的配位行为。结果表明，Ｌ’以二齿的形式和 Ｃｕ（Ⅱ）形成稳定的 ２：１（Ｌ： Ｍ）配合物。其配位水分子的离解常数 ｐ Ｋａ为 ７．５４。对于 ＨＬ~２，三个氮原子和酚氧负离子与 Ｃｕ（Ⅱ）配位，酚羟基离解常数 ｐ Ｋａ为４．４４。在２５±０．１℃，Ｉ＝０．１（ＫＮＯ_３）条件下，ｐＨ＝６～９（５０ｍｏｌ·Ｌ~（－１））范围内，用紫外、可见分光光度法研究了Ｌ~１的Ｃｕ（Ⅱ）配合物催化对－硝基苯酚乙酸酯（ＮＡ）水解动力学行为，发现配合物催化ＮＡ酯水解反应速率常数ｋ_（ＮＰ）与溶液 ｐＨ呈 Ｓｉｇｍｏｉｄａｌ型曲线， ｋ_（ＮＰ）最大值为 ２． ５３×１０~（－２）Ｌ· ｍｏｌ(－１)· ｓ(－１)。说明 Ｌ~１的 Ｃｕ（Ⅱ）配合物中的 Ｃｕ（Ⅱ）－ＯＨ~－是有效的亲核试剂，对底物ＮＡ酯的水解有较好的催化作用。
The effects of Cu (Ⅱ) and tripyridyl amine (L ’) and the team (2’-hydroxybenzyl) were studied by pH potentiometric titration at 25 ± 0.1 ℃ T and I = 0.1 (KNO 3) Coordination Behavior of Diethylenediamine (HL ~ 2). The results show that L ’forms a stable 2: 1 (L: M) complex with Cu (Ⅱ) in bidentate form. The dissociation constant p Ka of coordination water is 7.54. For HL ~ 2, three nitrogen atoms and phenolic anions coordinate with Cu (Ⅱ), the dissociation constant of phenolic hydroxyl group, p Ka, is 4.44. Under the conditions of 25 ± 0.1 ℃, I = 0.1 (KNO 3) and pH = 6 ~ 9 (50 mol·L -1), UV and visible spectrophotometry were used to study the effects of L 1 The kinetics of the hydrolysis of p-nitrophenol acetate (NA) catalyzed by Cu (Ⅱ) complexes showed that the complex catalyzed the hydrolysis reaction of NP with the Sigmoidal curve and the k_ (NP) The value is 2. 53 × 10 ~ (-2) L · mol (-1) · s (-1). This indicates that Cu (Ⅱ) -OH ~ - in L ~ 1 Cu (Ⅱ) complex is an effective nucleophile and catalyzes the hydrolysis of the substrate NA ester.