【摘要】 对系列手性salen-Ni（Ⅱ）络合物的电子圆二色（ECD）光谱及其绝对构型关联进行了概述.根据晶体结构和对固、液ECD光谱的表征,结合理论计算,着重探讨了准平面型手性[Ni（salen）]的固态结构及其在溶液中的绝对构型和优势构象.在此基础上通过若干实例说明了平面四方形[M（Salen）]络合物两种绝对构型命名法,并给出了我们的建议.对[Ni（sal-R,R-chxn）][sal-R,R-chxn=（R,R）-N,N’-双（亚水杨基）-1,2-二亚氨基环己烷]的二氯甲烷溶液ECD光谱的计算结果表明,可见区第一个ECD吸收带主要是π→d荷移跃迁（LMCT）所致,而不是通常认为的d-d跃迁:[Ni（sal-R,R-chxn）]的绝对构型为∧,其在可见区第一个ECD吸收带为正.将此ECD指纹应用于具有"闭壳层"电子结构的其它平面型手性[Ni（Salen）]和六配位trans-[Co^Ⅲ（salen）L₂]络合物的绝对构型指认,具有一定的普适性.本文的研究结果对于深入理解手性[M（Salen）]络合物的配位立体化学、手征光学性质及其手性识别和不对称催化机理具有重要科学意义.更多还原

【Abstract】 A correlation between the electronic circular dichroism（ECD） spectra and the absolute configurations of a serials’ chiral salen-Ni（Ⅱ） complexes was investigated.The solid-state structures,absolute configurations,and preferential conformations in solution of quasi-planar chirai[Ni（salen）]complexes were studied using their crystal structures,solid-state and solution ECD spectra in combination with theoretical ECD calculations.Furthermore,two different nomenclatures for the absolute configurations of square-planar[M（salen）]complexes were inspected carefully,and suggestions for proper use of them are discussed.The calculated ECD spectra of[Ni（sal-R,R-chxn）][sal-R,R-chxn =（R,R）-1,2-cyclohexylene bis（salicylicdeneiminate）]in dichloromethane solution revealed that the first ECD band in the visible region was dominated by the ligandto-metal charge transfer transition（LMCT）,which was incorrectly assigned to a d-d transition in the literature.When the absolute configuration of[Ni（sal-R,R-chxn）]was A,the first ECD absorption band in the visible region was positive.This ECD fingerprint is universally applicable for assigning the absolute configurations of other square-planar chiral[Ni（salen）]and six-coordinate trans-[Co^Ⅲ（salen）L₂]complexes with a "closed-shell" electronic structure.This work provides some insight into the coordination stereochemistry and chiroptical properties of chiral[M（salen）]complexes.Additionally,this work is significant for the understanding of chiral recognition and asymmetric catalytic mechanisms.更多还原