Polyarylcyanation of Diyne: A One-Pot Three-Component Convenient Route for In Situ Generation of Polymers with AIE Characteristics

A facile, one-pot, three-component polymerization route for in situ generation of polymers with aggregation-induced emission (AIE) characteristics was developed. The polycoupling of dibromoarenes, internal diynes and potassium ferrocyanide was catalyzed by palladium acetate and sodium bicarbonate and proceeded smoothly in dimethylacetamide under nitrogen at 120 °C, producing poly­(triphenylacrylonitrite)­s (PTPANs) with high weight-average molecular weights of up to 223000 in high yields of up to 84%. This polymerization method enjoys the remarkable advantages of high reaction rate and efficiency and broad monomer scope. Model reaction was carried out to aid the structure characterization and property investigation of the obtained polymers. All the polymers show remarkable thermal stability, losing merely 5% of their weight at high temperature of up to 513 °C. They are soluble in common organic solvents and their spin-coated thin films exhibit high refractive indices (1.6482–1.7682). Thanks to the triphenylethene chromophore in situ generated during the polymerization, all the polymers are AIE-active and show strong light emission in the solid state. While UV irradiation of the polymer thin films in air through upper masks photo-oxidizes the exposed parts and quenches their light emission, the unexposed parts remain emissive. Two-dimensional fluorescent patterns with good resolution are thus generated.