摘要
室温下在甲醇-水(1:1)的混合体系中测定了两端连有8-羟基喹啉、2-甲基-8-羟基喹啉基生色团的非手性开链冠醚与碱金属盐形成配合物的裂分圆二色性,发现裂分的Cotton效应是由生色团的~1B_b跃迁偶间的偶合所致。依负激子手性和激子手性规则,推断出冠醚配合物为右手螺旋结构,按R/S系统命名为P型立体化学。同时还讨论了盐及冠醚链长对裂分Cotton效应的影响。
The CD alkali metal complexes of achiral open-chain crown ether(Ⅰ—Ⅳ) with two quinoline chromophores were measured in MeOH-H_2O(1:1) solution at room temperature. It was found that the coupling of two ~1B_b transition moments exhibited split cotton effect of opposite signs. The direction of electric transition was polarized along the long axis of chromophore. Therefore, the right-handed screwn structures could be depicted according to the negative excition chirality and excition chirality rule. The R/S nomenclature is P absolute configuration. The effects of salt and chain length on split CD were also discussed.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
1990年第4期16-19,49,共5页
Spectroscopy and Spectral Analysis
