Helix-sense-selective copolymerization of phenyl[bis(2-pyridyl)]methyl methacrylate,diphenyl(2-pyridyl)methyl methacrylate and triphenylmethyl methacrylate with chiral anionic initiators

Optically active polytriphenylmethyl methacrylate-co-phenylbis(2-pyridyl)]methyl methacrylate] (polyTrMA-co-PB2PyMA], polydiphenyl(2-pyridyl)methyl methacrylate-co-phenylbis(2-pyridyl)]methyl methacrylate] (polyD2PyMA-co-PB2PyMA]), and polytriphenylmethyl methacrylate-co-diphenyl(2-pyridyl)-methyl methacrylate] (polyTrMA-co-D2PyMA]) were prepared by helix-sense-selective copolymerization with complexes of organolithium with (?)-sparteine (?)Sp],(S, S)-(+)- and (R, R)-(?)-2,3-dimethoxy-1,4-bis(dimethylamino)butane (+)- and (?)DDB], and (S)-(+)-2-(1-pyrrolidinylmethyl)pyridine (+)PMP] as anionic initiators in toluene at low temperature. The copolymers obtained with (?)Sp and (+)DDB or (?)DDB complexes of organolithium showed low optical activity, but to (+)PMP] complex with N,N′-diphenyleneamine monolithium amide (+)PMP–DPEDA–Li)] was effective in synthesizing copolymers of high optical rotation (α] about +320 to + 370°) which were comparable to those of corresponding homopolymers with one-handed helical structure. The optical rotations of polyTrMA-co-PB2PyMA] and polyTrMA-co-D2PyMA] were much more stable than that of poly(D2PyMA) or poly(PB2PyMA) in a solution of CHCl₃–2,2,2-trifluoroethanol (10 : 1, v/v) at 25°C, but optical rotation of polyD2PyMA-co-PB2PyMA] slowly decreased with time in the same conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2127–2133, 1998