An attempt to synthesize star-type conjugated polymer, poly(arylene ethynylene), formed by palladium-catalyzed coupling of π-conjugated oligomeric poly(arylene ethynylene) with 1,3,5-triethynylbenzene and 1,2,4,5-tetraethynylbenzene

Addition of 1,3,5-triethynylbenzene or 1,2,4,5-tetraethynylbenzene to a reaction system containing π-conjugated oligomeric poly(arylene ethynylene) gives polymers with very high molecular weights, which are considered to have star-type structures. The polymers exhibit a photoluminescence peak at 457 ± 2 nm with a quantum yield of 35 ± 4%.