Liu Y, Chen Y, Liu S X, Guan X D, Wada T, Inoue Y
Department of Chemistry, Nankai University, Tianjin, 300071, China.
Org Lett. 2001 May 31;3(11):1657-60. doi: 10.1021/ol015820a.
Newly synthesized bis(beta-cyclodextrin-6-yl) 2,2'-bipyridine-4,4'-dicarboxylate was found to induce an unusual fluorescence enhancement of Rhodamine B (RhB) upon complexation. This effect is attributable to the equilibium shift of RhB to the highly fluorescent carboxylate ion form, which is induced by the cooperative binding by two appropriately preorganized cyclodextrin units in the bis(beta-cyclodextrin). This sandwich complexation behavior was investigated by means of the fluorescence and 2D NMR spectroscopy.
新合成的双(β-环糊精-6-基)2,2'-联吡啶-4,4'-二羧酸酯被发现与罗丹明B(RhB)络合时会诱导出异常的荧光增强。这种效应归因于RhB向高荧光羧酸盐离子形式的平衡转移,这是由双(β-环糊精)中两个适当预组织的环糊精单元的协同结合所诱导的。通过荧光和二维核磁共振光谱研究了这种夹心络合行为。