Synthesis and asymmetric anionic polymerization of substituted 7-aryl-2,6-dimethyl-1,4-benzoquinone methides

Article abstract of DOI:10.1002/pola.27449

Substituted 7-aryl-2,6-dimethyl-1,4-benzoquinone methides which have an electron-donating methoxy substituent at the para-position (p-OMe, 2a) or an electronwithdrawing chloro one at the para- (p-Cl, 2b), meta- (m-Cl, 2c), and ortho-positions (o-Cl, 2d) of the benzene ring were synthesized, and their asymmetric anionic polymerizations using the complex of lithium 4-isopropylphenoxide with (-)- sparteine were carried out in toluene at 0°C. The polymers with negative specific rotation were obtained for all of four monomers, and the polymer obtained from 2a showed smaller specific rotation value than that of polymer having no substituent (p-H, 1) on the phenyl group and the polymers obtained from 2b-d showed larger ones. It was found that the kind of a substituent and its substitution position on the phenyl group affect significantly the optical activity of polymers. The largest specific rotation value of [α]₄₃₅= -153.2° was obtained in the polymerization of 2d with an ortho-chloro substituent.