Asymmetric Michael Addition of Ketones to Nitroolefins Catalyzed by a New Chiral Catalyst
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چکیده
منابع مشابه
Chiral phosphoproline-catalyzed asymmetric Michael addition of ketones to nitroolefins: an experimental and theoretical study.
A novel pyrrolidine-based chiral phosphoproline is an effective bifunctional organocatalyst for the asymmetric Michael addition of ketones to nitroolefins giving high levels of diastereo- and enantio-selectivities (up to > 99 : 1 dr and 96% ee). anti-SR Transition state has the lowest barrier which controls the stereoselectivity, in agreement with experimental results.
متن کاملAsymmetric Michael addition of ketones to nitroolefins: pyrrolidinyl-oxazole-carboxamides as new efficient organocatalysts.
Chiral pyrrolidinyl-oxazole-carboxamides were synthesized and used as efficient new organocatalysts for the asymmetric Michael addition of ketones with nitroalkenes under solvent-free conditions. Gratifyingly, the corresponding Michael adducts were obtained in higher yields (up to 99%) and excellent stereoselectivities (up to >99/1 dr and 99% ee). Transition state models have been proposed to a...
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The current work reports an organocatalytic strategy for the asymmetric catalysis of chiral benzofuran-2(3H)-ones bearing 3-position all-carbon quaternary stereocenters. Accordingly, highly enantioselective Michael addition reactions of 3-substituted benzofuran-2(3H)-ones to nitroolefins have been developed by utilizing a bifunctional tertiary-amine thiourea catalyst. The reactions accommodate ...
متن کاملAsymmetric organocatalytic Michael addition of ketones to vinyl sulfone.
Highly enantioselective organocatalytic Michael addition of ketones to vinyl sulfone catalyzed by a cinchona alkaloid-derived primary amine is reported for the first time; the described synthetic methodology was applied to the synthesis of sodium cyclamate.
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ژورنال
عنوان ژورنال: Bulletin of the Korean Chemical Society
سال: 2010
ISSN: 0253-2964
DOI: 10.5012/bkcs.2010.31.5.1280