Isomeric [2]Rotaxanes and Unidirectional [2]Pseudorotaxane Composed of α-Cyclodextrin and Aliphatic Chain-Linked Carbazole-viologen Compounds
作者:Joon Woo Park、Hyun Jung Song
DOI:10.1021/ol048079q
日期:2004.12.1
DMF gives two isomeric [2]rotaxanes, 2a and 2b, while alpha-CD and 1-(N-carbazole)-10-[4-(1-methyl-4-pyridnino)-1-pyridinio]decane 3 in water form mostly a unidirectional [2]pseudorotaxane having the same alpha-CD orientation as 2b. Structures were elucidated from 1H NMR and circular dichroism spectra. The orientational specificity of alpha-CD in the 3/alpha-CD [2]pseudorotaxane is due to the slow dethreading
[结构:见正文]用3,5-二甲氧基苄基溴将1-(N-咔唑)-10- [4-(4-吡啶基)-1-吡啶基]癸烷的α-环糊精(α-CD)配合物封端DMF产生两种异构的[2]轮烷,2a和2b,而α-CD和1-(N-咔唑)-10- [4-(1-甲基-4-吡啶基)-1-吡啶基]癸烷3呈水形式大多数是单向[2]伪轮烷,其α-CD取向与2b相同。从1 H NMR和圆二色性光谱阐明了结构。3 /α-CD[2]假轮烷中α-CD的定向特异性是由于2b型异构体的慢脱线速率所致。