摘要
A complexation study on the new Zn(II) complexes of asymmetric tripodal ligand 2-[bis(2-aminoethyl)amino]ethanol (L) has revealed that the alcoholic OH group of complex ZnL exhibits remarkable acidity with a very low pKa value of 7.7 at 25 °C. Both the monomeric complex [ZnH-0.25L(H2O)](ClO4)1.75 (I) and the dimeric alkoxide-coordinating complex [Zn2(H-1L)2](ClO4)2 (II) were synthesized, and their structures were determined by X-ray diffraction. The Zn(II)-bound alkoxide, as the reactive nucleopile toward the hydrolysis of esters, has shown a second-order rate constant of 0.13 ± 0.01 M-1 s-1 in 10% (v/v) CH3CN at 25 °C in 4-nitrophenyl acetate (NA) hydrolysis, which is almost the same as the corresponding value for the very reactive alcohol-pendent [12]aneN3-Zn complex. Present work shows for the first time that Zn(II) complexes of the asymmetric tripodal polyamine bearing an ethoxyl pod can also serve as good models of Zn(II)-containing enzymes.
源语言 | 英语 |
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页(从-至) | 2394-2401 |
页数 | 8 |
期刊 | Inorganic Chemistry |
卷 | 40 |
期 | 10 |
DOI | |
出版状态 | 已出版 - 7 5月 2001 |
已对外发布 | 是 |