Poly(p‐phenylene)s with polar side groups, 1. Pd‐catalyzed synthesis, characterization and modification of poly(p‐phenylene)s bearing butoxymethyl side chains

This is a description of the Pd‐catalyzed synthesis of two poly(p‐phenylene) (PPP) derivatives which have butoxymethyl side groups on each, or every alternate, phenylene moiety. For the latter, details are given of the quantitative transformation of the ether functionalities into bromomethyl pendant groups. Subsequent reaction of these bromo functionalities with sodium 4‐cyanophenolate or sodium acetate produced structurally homogeneous PPP's which had 4‐cyanophenoxymethyl and acetoxymethyl side groups, respectively. The PPP derivatives described here are soluble in common organic solvents and were characterized in detail by NMR spectroscopy, membrane osmometry and size exclusion chromatography (SEC). The degrees of polycondensation of the butoxymethyl‐substituted polymers were found to be in the order of 30–65. No evidence for chain degradation during the following conversions was found on the basis of the NMR and SEC measurements.