Synthesis of conducting polymers with conjugated carbon-carbon triple bonds by electrochemical condensation of acetylene derivatives catalyzed by copper complex

Acetylene derivatives were electrolyzed at + 1.5 V (vs. SCE) in the presence of copper (I) salt and N,N,Nʹ,Nʹ-tetra-methylethylenediamine at 40 °C under an argon atmosphere. Phenylacetylene was oxidatively coupled to diphenylbutadiyne quantitatively. In the case of 1,4-diethynylbenzene, soluble poly(phenylenebutadiynylene) was obtained. The electrical conductivity (σ) increased from 10−14 S cm−1 to 10−12 S cm−1 after I2 doping. In the case of acetylene as the substrate, an insoluble black powdery product was obtained. The IR spectrum of the product was similar to that of carbyne reported before.