Catechol-based macrocyclic aromatic ether-sulfones: synthesis, characterization and ring-opening polymerization

Cyclocondensation between 4,4'-bis(4"-chlorobenzenesulfonyl)biphenyl and catechol, with subsequent chromatographic separation of the reaction products, led to the isolation of four novel ether-sulfone macrocycles (cyclic dimer, -trimer, -tetramer and -pentamer). Similarly, cyclocondensation of catechol with a novel seven-ring diketone/disulfone monomer allowed the isolation of the two new aromatic ether-ketonesulfone macrocycles, a cyclic monomer and a cyclic dimer. Transannular shielding and deshielding effects in the cyclic monomer produce substantial chemical shift differences for chemically equivalent protons in the 1 H NMR spectra of the cyclic monomer and -dimer. Fluoride-initiated ring-opening polymerization of the ethersulfone cyclic trimer affords a novel, high-molecular weight poly(ether-sulfone).