Sparteine complexes Grignard reagents

Y. Okamato, K. Suzuki, T. Kitayama, H. Yuki, H. Kageyama, K, Miki, N. Tanaka, and N. Kasai, Kinetic resolution of racemic methylbenzyl methacrylate Asymmetric selective polymerization catalysed by Grignard reagent-(-)-sparteine derivative complexes, /. Am, Chem, Soc., 104 4618 (1982). 

Several optically active polymers of acrylates and methacrylates have been obtained by enantioselective polymerization of a racemic monomer initiated by a Grignard compound complexed with chiral reagent. Complexing agents for the polymerization of (K,S)-a-methylbenzyl methacrylate include chiral alcohols, such as quinine and cinchonine [63], (— )-sparteine and its derivatives [64-67], and other axially disymmetric biphenyl compounds [68,69]. Other racemic monomers used include (/ ,S)-a-methylbenzyl acrylate [70], (K,S)-l-phenylethyl acrylate, methacrylate and a-ethylacrylate [71], and 1,2-diphenylethylmethacrylate [72]. 

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