[2]Pseudorotaxanes Based on the Recognition of Cryptands to Vinylogous Viologens

Host–guest complexation between two crown ether-based cryptands and two vinylogous viologens has been studied. Formation of [2]pseudorotaxanes from a dibenzo-24-crown-8-based cryptand and these vinylogous viologens can be reversibly controlled by adding and removing potassium cation in acetone. Furthermore, the complexation between a bis(m-phenylene)-32-crown-10-based cryptand and a vinylogous viologen exhibits a high association constant, 1.18 × 106 M–1 in acetone, and leads to the formation of a supramolecular poly[2]pseudorotaxane in the solid state.本研究针对两种冠醚基穴状配体（crown ether-based cryptands）与两种插烯紫精（vinylogous viologens）之间的主客体络合（Host–guest complexation）行为展开了系统探究。由二苯并-24-冠-8（dibenzo-24-crown-8）基穴状配体与上述插烯紫精构建的[2]准轮烷（[2]pseudorotaxanes），可通过在丙酮体系中添加或移除钾离子实现可逆调控。此外，双(间亚苯基)-32-冠-10（bis(m-phenylene)-32-crown-10）基穴状配体与插烯紫精之间的络合反应在丙酮体系中展现出1.18 × 10^6 M–1的高结合常数（association constant），并可在固态下生成超分子聚[2]准轮烷（supramolecular poly[2]pseudorotaxane）。