Supramolecular Pseudorotaxane Polymers from Biscryptands and Bisparaquats

Five new bis(dibenzo-30-crown-10-based cryptand)s were synthesized, two of which (16 and 17) had long (12-atom), flexible spacers that led to cooperative complexation of dibenzyl paraquat TFSI (K-ave = 4.36 X 10(5) M-1 for 17.2b). Self-assembly of 16 and 17 with bisparaquats with similar spacers (18, 21, and 23) led to high molecular weight supramolecular pseudorotaxane polymers in solution. Continuous, flexible fibers were drawn from concentrated solutions. 17 with C-10-linked bisparaquat 23 in dichloromethane (DCM) produced a log-log viscosity vs concentration plot with a limiting slope of 3.55, confirming high molecular weight; at 37 mM, the degree of polymerization was estimated to be 126 and M-n = 407 kDa. These are the first truly polymeric pseudorotaxane-type AA/BB supramolecular polymers.