Enantio- and diastereoselective, stereospecific mannich-type reactions in water
Tomoaki Hamada1, Kei Manabe, Shu Kobayashi
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
Catalytic asymmetric Mannich-type reactions in water proceeded in high yields and selectivities using a combination of ZnF2 and a chiral diamine that has the methoxy groups on the aromatic rings. In these reactions, either syn- or anti-Mannich adducts were stereospecifically obtained from (E)- or (Z)-silicon enolate, in contrast with most asymmetric Mannich-type reactions.
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