Three bis-p-phenylene-34-crown-10 (BPP34C10) derivatives bearing ester groups on one or both of their two aromatic rings have been synthesized. These ester-substituted macrocyclic polyethers bind the paraquat dication in solution more strongly than BPP34C10. In contrast, however, acyclic analogs of these macrocyclic polyethers form much weaker complexes with cyclobis (paraquat-p-phenylene)(CBPQT4+). Likewise, catenane ...
