Stimuli‐responsive chiral polyacetylene based on copolymerization of N ‐propargylamide and propargylether

Copolymerization of propargylether having antipyrine group (PT) and N ‐( tert ‐butoxycarbonyl)‐ l ‐valine‐ N ‐propargylamide (LA) was conducted with (nbd)Rh + [ η 6 ‐C 6 H 5 B − (C 6 H 5 ) 3 ] as a catalyst to obtain novel antipyrine‐functionalized chiral copolymer. The controllable secondary structure of the copolymers by different unit ratio or solvent environment led to a controlled fluorescence of the side‐chain antipyrine. Poly(LA 88 ‐ co ‐PT 12 ) exhibited a large specific rotation and a circular dichroism (CD) signal, while it emitted very stronger fluorescence. From CD and ultraviolet–visible spectra, the regular structure of poly(LA 88 ‐ co ‐PT 12 ) was destroyed, and the random coil was formed with temperature increase. The helical conformation of poly(LA 75 ‐ co ‐PT 25 ) disappeared by the addition of MeOH to CHCl 3 solution, while the fluorescence signal also became weaker than in CHCl 3 solution. It is suggested that the copolymer conformation much influenced the performance of chromophores. In the present study, the helix conformation could induce fluorescence enhancement. Copyright © 2015 John Wiley & Sons, Ltd.