Preparation of hyperbranched copolymers constituted of triphenylamine and phenylene units

The Pd-catalyzed coupling of tris(4-bromophenyl)amine 1 and benzene-1,4-diboronic acid 2 gave a hyperbranched conjugated copolymer 3 in a one step process and in a high yield. Polymer 3 was soluble in organic solvents such as THF and chloroform. GPC indicated that it had an average molecular weight of 5.4x10 3 . A cast film had an anodic peak at 1.2 V vs Ag wire. It was green above the oxidation potential and brown-yellow in the neutral state.