Asymmetric polymerization of methacrylates

The syntheses of optically active polymers having helical conformation from bulky methacrylates are reviewed focusing on selected topics. The monomers include triphenylmethyl methacrylate and its analogues. Asymmetric anionic polymerization of the monomers gives isotactic, optically active polymers having a helical structure with excess helicity, The isotactic content and the extent of helical-sense excess depend on the monomer structure and the reaction conditions. In the case of methacrylates, completely isotactic and single-handed helical polymers can be produced by asymmetric anionic polymerization (helix-sense-selective polymerization). Asymmetric radical polymerization is also possible for this class of monomer. Some of the helical polymers show chiral recognition ability coward a wide range of racemic compounds. Polymers having main-chain configurational chirality are also discussed.