Anionic polymerization of 4-phenyl-1-buten-3-yne derivatives bearing electron-withdrawing groups

The anionic polymerization of derivatives of 4-phenyl-1-buten-3-yne was carried out to investigate the effect of substituents on the polymerization behavior. The polymerization of 4-(4-fluorophenyl)-1-buten-3-yne and 4-(2-fluorophenyl)-1-buten-3-yne in tetrahydrofuran at −78 °C with n-BuLi/sparteine as an initiator gave polymers consisting of 1,2- and 1,4-polymerized units in quantitative yields with ratios of 80/20 and 88/12, respectively. The molecular weights of the polymers were controlled by the ratio of the monomers to n-BuLi, and the distribution was relatively narrow (weight-average molecular weight/number-average molecular weight < 1.2), supporting the living nature of the polymerization.