Novel Soluble and Fluorescent Poly(arylene ether)s Containing p-Quaterphenyl, 2,5-Bis(4-phenylphenyl)oxadiazole, or 2,5-Bis(4-phenylphenyl)triazole Groups

Three novel conjugated biphenols 3, 4, and 8 were synthesized by the Pd(OAc) 2 -catalyzed regioselective carbon−carbon coupling reaction of 2,6-di- tert -butylphenol or 2-phenylphenol with aryl halides. Although poly(arylene ether)s derived from biphenol 3 and arylene difluorides have low solubility in organic solvents, using 4,4‘-(9-fluorenylidene)diphenol or 4,4‘-(hexafluoroisopropylidene)diphenol as a comonomer gave soluble poly(arylene ether)s 6a − c . High molecular weight poly(arylene ether)s 7a ‘ − c ‘ were also prepared from biphenol 4 . The biscarbamate-masked monomers 5 and 9 improved the polymerization to give higher molecular weight polymers 7a − e and 10a − e in higher yields. Polymers 7 and 10 possess better film-forming capabilities and are still soluble in organic solvents. Polymers 6, 7, and 10 are all thermally stable with 5% weight loss temperatures higher than 500 °C under nitrogen. The polymers show strong blue light emission ranging from 387 to 478 nm in solution, depending on the conjugated structure.