Journal of Polymer Science Part A: Polymer Chemistry, Vol.50, No.4, 772-779, 2012
Synthesis of fac-Ir(ppy)(3) end-functionalized poly(1,3-cyclohexadiene): single monomer addition of fac-Ir(ppy)(2)(vppy) for well-controlled polymer synthesis
Synthesis of the polymer whose end is functionalized by fac-Ir(ppy)(3) (ppy = 2-phenylpyridyl) was achieved by using (living) anionic polymerization of 1,3-cyclohexadiene: the reaction of poly(1,3-cyclohexadienyl)lithium (PCHDLi) with fac-Ir(ppy)(2)(vppy) [vppy = 2-(4-vinylphenyl)pyridyl] resulted in nucleophilic attack of the carbanion in PCHDLi on the vinyl group of fac-Ir(ppy)(2)(vppy) selectively. Complexation of the pyridyl ring protected the alpha-carbons of fac-Ir(ppy)(2)(vppy) from the reaction of the anionic polymer. The homopolymerization of fac-Ir(ppy)(2)(vppy) did not occur, and only one molecule of fac-Ir(ppy)(2)(vppy) reacted with the carbanion of PCHDLi and was selectively incorporated into an end of poly(1,3-cyclohexadiene) (PCHD). Thus, the PCHD with fac-Ir(ppy)(3) end-group was obtained with a well-controlled and defined polymer structure and molecular weight. (c) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 772-779, 2012
Keywords:anionic polymerization;functionalization of polymers;high performance polymers;living polymerization;monomers