Synthesis of polymeric topological isomers through electrostatic self-assembly and covalent fixation with star telechelic precursors

摘要

A pair of macromolecular constitutional isomers having topologically distinctive, dicyclic constructions, that is, theta-shaped and manacle-shaped polymers, has been synthesized from a polymer self-assembly, comprised of three-armed star poly(tetrahydrofuran) poly(THF) having N-phenylpyrrolidinium salt end groups carrying dicarboxylate counteranions (1S/2d). The presence of the two constitutional polymeric isomers was confirmed by means of a reversed-phase liquid chromatography (RPC) technique. Moreover, size exclusion chromatography (SEC) showed that a major component possesses notably larger hydrodynamic volume than the others, and is assignable as a manacle-shaped isomer while a minor component is assigned as a theta-shaped isomer. The statistics of the covalent-linking process of 1S/2d were consistent with the other experimental results.