Quinine-catalyzed highly enantioselective cycloannulation of o-quinone methides with malononitrile.
نویسندگان
چکیده
2-Amino-3-cyano-4H-chromenes show great potential as novel anticancer agents. Here we report a quinine-catalyzed highly enantioselective formal 4 + 2 cycloaddition of ortho-quinone methides and malononitrile, providing a unique approach to 4-arylvinyl, 4-aryl and 4-vinyl 2-amino-3-cyano-4H-chromenes with excellent yields and enantioselectivities. Moreover, this reaction can be performed in up to 6 mmol scale without any noticeable loss of yield and stereoselectivity.
منابع مشابه
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 13 8 شماره
صفحات -
تاریخ انتشار 2015