Asymmetric anionic polymerization of 2,6-dimethyl-7-phenyl-1,4-benzoquinone methide

Asymmetric anionic polymerizations of 2,6-dimethyl-7-phenyl-1,4-benzoquinone methide ( 1 ) were performed with various chiral anionic initiators, and the specific rotations of the obtained polymers were investigated. Optically active poly( 1 )s with configurational chirality were obtained with all the initiators, and a complex of fluorenyllithium (FlLi) with (?)-sparteine (?)-Sp] produced poly( 1 ) with the largest negative specific rotation (α]₄₃₅ = ?26.8°). The specific rotations of poly( 1 )s obtained with FlLi/(?)-Sp depended on the initiator concentration and the solvent polarity. The maximum specific rotations were obtained at an almost constant initiator concentration (ca. 0.03 mol/L), regardless of the monomer concentration, in toluene, whereas a higher initiator concentration was required in more polar solvents. These results suggested that the aggregation state of the propagating chain end significantly affected the specific rotation of poly( 1 ). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4548–4555, 2004