Synthesis of a Photoresponsive Cryptand and Its Complexations with Paraquat and 2,7-Diazapyrenium

A McMurry coupling reaction was used for the efficient synthesis of a bis­(m-phenylene)-32-crown-10 based cryptand Z-3 with high yield. This photoresponsive cryptand formed host–guest complexes with paraquat derivative 4 and 2,7-diazapyrenium derivative 5. Z-3, and E-3 exhibited similar binding affinity to the small guest 4, while dramatic changes were observed in the binding affinity to the large guest 5.