[Co(tp)~2(Me-en)]ClO~4配合物不对称氮的翻转及重氢化动力学研究

本文合成了Co(tp)~2(Me-en)]ClO~4(tp:2-羟基-2,4,6-环庚三烯-1-酮负离子;Me-en:N-甲基乙二胺)三元不对称配合物, 用离子交换法分离了该配合物的Λ(R)△(S)和Λ(S)△(R)两对对映体, 用高效液相色谱法测定了对映体的不对称配位氮的翻转速率常数k~e~p(差向立体异构化速率常数), 用^1HNMR法测定了对映体的不对称配位氮的重氢化质子交换)速率常数k~D, 并与同属CoO~4~2型的NaCo(OX)~2(Me-en)](OX:草酸根)、Co(acac)~2(Me-en)]ClO~4(acac:2,4-戊二酮负离子)配合物的k~e~p、k~D值进行了比较, 讨论了影响质子交换、不对称氮翻转速率的因素及反应机理。

The kinetic studies on inversion and deuteration at the chiral nitrogen center of [Co(tp)~2(Me-en)]^+

Co(tp)2(Me-en)]ClO4 (Htp = tropolone, Me-en = N-methylethylenediamine) was prepared and L(R)D(S) and L(S)D(R) epimers were separated by ion exchange. Rates of base catalyzed reversible epimerization and deuteration at the chiral N center were detd in aqueous solns. by HPLC and NMR, resp. Results are compared with those of Co(ox)2(Me-en)]- (H2ox = oxalic acid) and Co(acac)2(Me-en)]+ (Hacac = acetylacetone). Factors influencing the reactions and their mechanisms are discussed.