Premium
Highly Enantioselective 1,4‐Michael Additions of Nucleophiles to Unsaturated Aryl Ketones with Organocatalysis by Bifunctional Cinchona Alkaloids
Author(s) -
Oliva Cristina G.,
Silva Artur M. S.,
Resende Diana I. S. P.,
Paz Filipe A. A.,
Cavaleiro José A. S.
Publication year - 2010
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.201000273
Subject(s) - enantioselective synthesis , chemistry , organocatalysis , nitromethane , cinchona , bifunctional , malononitrile , aryl , nucleophile , organic chemistry , cinchona alkaloids , squaramide , michael reaction , catalysis , combinatorial chemistry , alkyl
The development of general and efficient asymmetricorganocatalytic additions of malononitrile and nitromethane to 1,5‐diarylpenta‐2,4‐dien‐1‐ones (cinnamylideneacetophenones) catalyzed by cinchona organocatalysts is reported. The reactions afforded excellent enantioselectivities (up to 99 %), high yields (up to 97 %), and exclusive 1,4‐addition regioselectivities. The potential of these new enantioselective additions lies in the demonstration that organocatalysts bearing primary amino groups in combination with TFA provide effective catalytic systems for the activation of a broad range of aryl ketones under mild conditions to give compounds with high levels of enantioselectivity and yields.