3-Bromooxindoles as nucleophiles in asymmetric organocatalytic Mannich reactions with N-Ts-imines.
نویسندگان
چکیده
A direct asymmetric Mannich reaction of N-unprotected 3-bromooxindoles with N-Ts-imines catalyzed by bifunctional thiourea derived from 2-substituted cinchona alkaloid was developed. Products with vicinal chiral tertiary and brominated quaternary stereogenic centers were achieved in excellent diastereo- and enantioselectivity (up to 99 : 1 dr, 99% ee).
منابع مشابه
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ورودعنوان ژورنال:
- Chemical communications
دوره 49 13 شماره
صفحات -
تاریخ انتشار 2013