New fluorescent monomers and polymers displaying an intramolecular proton‐transfer mechanism in the electronically excited state (ESIPT). IV. Synthesis of acryloylamide and diallylamino benzazole dyes and its copolymerization with MMA

Six new fluorescent monomers were synthesized by reaction of 2‐(5′‐amino‐2′‐hydroxyphenyl)benzazole derivatives with acryloyl chloride and allyl bromide. UV–vis and steady‐state fluorescence in solution were used to characterize its photophysical behavior. The monomers are fluorescent in the blue, green, yellow, and red region, with a large Stokes shift between 92 and 226 nm. A dual fluorescence ascribed to a conformational equilibrium in solution in the ground state dependent on the solvent polarity could be observed in the fluorescence emission spectra of the monomers. The radical polymerization of the monomers with methyl(methacrylate) allowed the production of fluorescent polymers in the blue–green region, with good optical and thermal properties.