Asymmetric Synthesis of Chiral Polymers by Means of Repetitive Addition of Allylsilane to Aldehyde

Abstract

Monomers having both allyltrimethylsilyl and formyl groups were prepared. Chiral (acyloxy)borane initiated the repetitive polyaddition of the monomers to give optically active polymers having main chain configurational chirality. Optical purity of the chiral polymer was evaluated by the analysis of the degradation product.

Key words

allylations - asymmetric catalysis - polymers - asymmetric polymerization - optically active polymers

References

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11

Benzaldehyde reacted with 1 equiv of methallyltrimethylsilane in the presence of 2 mol% of Sc(OTf)₃ at r.t. Quantitative conversion was attained when propionitrile was used as solvent. Although MeCN and nitromethane gave high conversion, other solvents such as CH₂Cl₂, DMF, toluene, nitroethane gave no product. THF was polymerized in the presence of Sc(OTf)₃.