Cation-reinforced donor-acceptor pseudorotaxanes
Cation-reinforced donor-acceptor pseudorotaxanes
复制标题
阳离子增强供体-受体拟轮烷
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
J. Sanders
中科院分区：
文献类型：
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作者：
S. Pascu;T. Jarrosson;C. Naumann;S. Otto;G. Kaiser;J. Sanders
本文报道了由富电子冠醚（主体1）、均苯四甲酸二酰亚胺（客体2）和碱金属盐模板MX（其中M = Li+和Na+，X− = Br−，I−，CF 3SO 3 −，[B（C6 F5）4]−和[B{3，5-（CF 3）2（C6 H3）}4]−）形成一系列准轮烷。将1和2在CH_2Cl_2或CHCl_3和MeOH（98∶2）的混合物中混合，得到浅黄色溶液，指示非常弱的电荷转移相互作用。添加MX后，由于红移和电荷转移带强度的增加，获得了色彩鲜艳的溶液。通过NMR对拟轮烷的结构和动力学进行了研究。[M2·1·2]2+的溶液相结构与X射线晶体学测定的固相结构一致。由于[Li 2·1]2+和[Li 2·1·2]2+的配位几何构型几乎完全重合，Li+对1·2配体-受体配合物具有显著的模板作用。
Formation of a series of pseudorotaxanes from an electron-rich crown ether (host 1), pyromellitic diimide (guest 2) and alkali salt templates MX, where M = Li+ and Na+, and X− = Br−, I−, CF3SO3−, [B(C6F5)4]− and [B{3,5-(CF3)2(C6H3)}4]−, is reported. Mixing of 1 and 2 in CH2Cl2 or a mixture of CHCl3 and MeOH (98∶2) gave a pale yellow solution indicative of a very weak charge-transfer interaction. Upon addition of MX, brightly coloured solutions were obtained, resulting from a red shift and an increase in the intensity of the charge-transfer band. Structural and kinetic studies of the pseudorotaxanes were performed by NMR. The solution-phase structures of [M2·1·2]2+ are in good agreement with the solid-phase structure determined by X-ray crystallography. The remarkable templating properties of Li+ for the 1·2 donor-acceptor complex are due to the almost perfect coincidence of coordinative geometries in [Li2·1]2+ and [Li2·1·2]2+.