C-H Oxidation/Michael Addition/Cyclization Cascade for Enantioselective Synthesis of Functionalized 2-Amino-4H-chromenes.
نویسندگان
چکیده
A streamlined method for the enantioselective synthesis of 2-amino-4H-chromenes from readily available 2-alkyl-substituted phenols and active methylene compounds bearing a cyano group with up to 97% ee is presented. This reaction is a cascade procedure including manganese dioxide mediated C-H oxidation for the generation of o-quinone methides and bifunctional squaramide-catalyzed Michael addition/cyclization.
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ورودعنوان ژورنال:
- Organic letters
دوره 17 24 شماره
صفحات -
تاریخ انتشار 2015