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合成并表征了在大环侧臂引入取代苯酚作为功能基团的新型四氮大环配体(L1,L2和L3).对配体L3的质子化过程及其与Zn(Ⅱ)的配位过程的研究表明,配体中的酚羟基与四氮大环环中的质子之间存在较强的氢键.测得配体及配合物中酚羟基的pKa分别为8.3和8.5.考察了上述3个配体的Zn(Ⅱ)配合物作为水解锌酶的模拟物催化对硝基苯酚乙酸酯(NA)水解的动力学行为,测得它们催化NA水解的二级反应速率常数kc/[(mol/L)(-1)·s(-1)]分别为3.48×10(-2)、1.52×10(-2)和2.85×10(-2).
Novel tetrazolium macrocyclic ligands (L1, L2 and L3) were synthesized and characterized by introducing substituted phenols as functional groups on the macrocyclic side arms. Protonation of ligand L3 and its coordination process with Zn (Ⅱ) show that there is a strong hydrogen bond between the phenolic hydroxyl group in the ligand and the proton in the tetrazolium ring. The measured pKa of the phenolic hydroxyl groups in the ligands and complexes were 8.3 and 8.5, respectively. The kinetics of the hydrolysis of p-nitrophenol acetate (NA) catalyzed by the Zn (Ⅱ) complexes of the three ligands as hydrolysates of zinc was investigated. The second-order reaction rate constants kc / [(mol / L) (-1) · s (-1)] were 3.48 × 10 -2, 1.52 × 10 -2 and 2.85 × 10 -2, .