Polymerization enantioasymmetric

Kassamaly, A. Sepulchre, M. Spassky, N. Enantioasymmetric polymerization of racemic styrene oxide. Polym. Bull. 1988, 79,119-122. 

In 1994, a highly efficient yttrium-based catalyst-yttrium 2-methoxyethoxide-was applied successfully to the polymerization of BL, with the reaction proceeding readily at room temperature [55]. When compared to diethylzinc/water or diethyl-zinc/methanol catalytic systems, the enantioasymmetric polymerization of racemic BL was also carried out in the presence of a diethylzinc/(R)-(-)-3,3-dimethyl-l,2-butanediol catalytic system (Scheme 9.18) [56]. 

A stereoelective (252, 299, 300) or asymmetric selective (298) or enantioasymmetric (301) polymerization where one of the enantiomers polymerizes in a preferential way in an ideal case 50% of the monomer is converted into a pure optically active polymer while the remainder is recovered as nonreacted compound also in the pure enantiomeric form (e.g., R -t- nS). ... 

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