高等学校化学学报 ›› 1998, Vol. 19 ›› Issue (5): 676.

• 论文 • 上一篇    下一篇

氮氧杂链型配体合成与Cu(Ⅱ)和Zn(Ⅱ)配位性质研究

解永树, 寇福平, 林瑞森, 宗汉兴   

  1. 浙江大学化学系, 杭州, 310027
  • 收稿日期:1997-06-07 出版日期:1998-05-24 发布日期:1998-05-24
  • 通讯作者: 解永树,男,26岁,博士研究生.
  • 作者简介:解永树,男,26岁,博士研究生.
  • 基金资助:

    国家自然科学基金

Synthesis of Linear Oxa-aza Ligands and Formation of Their Copper(Ⅱ) and Zinc(Ⅱ) Complexes

XIE Yong-Shu, KOU Fu-Ping, LIN Rui-Sen, ZONG Han-Xing   

  1. Department of Chemistry, Zhejiang University, Hangzhou, 310027
  • Received:1997-06-07 Online:1998-05-24 Published:1998-05-24

摘要: 合成了4种氮氧杂链型配体N,N'-二-(2-羟乙基)-乙二胺(L1)、N-(2-羟基苄基)-丙醇胺(HL2)、N-(2-羟乙基)-N'-(2-羟基苄基)-乙二胺(HL3)和N-(2-羟乙基)-二乙三胺-(L4),通过元素分析、IR和1H NMR等手段表征了其结构,用pH电位滴定法在25℃、I=0.10(KNO3)条件下,测定了L1和HL2与Cu(Ⅱ)离子以及HL3和L4与Zn(Ⅱ)离子配位平衡常数.结果表明:L1和HL2与Cu(Ⅱ)离子配位时,均可生成四配位配合物,其中第三配位点醇羟基配位较强,其质子离解常数pKa1分别为7.28和7.32;第四配位点是第2个醇羟基或1个水分子配位,其pKa2分别为9.33和9.04;HL3和L4与Zn(Ⅱ)均可生成五配位配合物,第四配位点均为醇羟基,其离解常数pKa1分别为7.76和7.96,第五配位点均为H2O,其pKa2分别为9.47和9.57.从上述热力学结果可见,配合物在中性pH值范围能生成亲核试剂Cu(Ⅱ)…-OR或Zn(Ⅱ)…-OR,而且均具备双重催化酯类底物水解的条件.

关键词: 不对称氮氧杂配体, 铜(Ⅱ)配合物, 亲核试剂, 模拟物

Abstract: Four linear oxa-aza ligands, N, N ′-bis-(2-hydroxyethyl)-ethylenediamine(L1), N-(2-hydroxybenzyl)-3-amino-1-propanol(HL2), N-(2-hydroxyethyl)-N ′-(2-hydroxy-benzyl)-ethylenediamine(HL3) and N-(2-hydroxyethyl) diethylenetriamine(L4), have been synthesized and characterized by elemental analyses, IR and 1H NMR. At (25±0.1) ℃, I=0.10(KNO3), complexation constants of Cu(Ⅱ) with L1 and HL2, and Zn(Ⅱ) with HL3 and L4 were determined by potentiometric pH-titration method. The results indicate that Cu(Ⅱ) forms four coordinated complexes with both L1 and HL2. Alkoxyl groups coordinate at the third coordination sites, with pKa1 values of 7.28 for L1 and 7.32 for HL2 to become alkoxide anions. While at the fourth sites were another alkoxyl or a water molecule with pKa2 values of 9.33 and 9.04 for L1 and HL2, respectively. Zn(Ⅱ) ions form five coordinated complexes with both HL3 and L4. The alkoxyl groups coordinate at the fourth sites with pKa1 values of 7.76 and 7.96. Water molecules at the fifth sites have pKa2 values of 9.47 and 9.57. From the above results, it can be seen that all these complexes yield nucleophiles Cu(Ⅱ)-…ORor Zn(Ⅱ)-…OR at neutral pH, and therefore fit the demand of double-catalysis for ester hydrolysis.

Key words: Unsymmetrical oxa-aza ligands, Copper(Ⅱ) complexes, Zinc(Ⅱ) complexes, Nuleophiles

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