Highly Diastereo- and Enantioselective Additions of Homoenolates to Nitrones Catalyzed byN-Heterocyclic Carbenes
نویسندگان
چکیده
منابع مشابه
A powerful synergistic effect for highly efficient diastereo- and enantioselective phase-transfer catalyzed conjugate additions.
An efficient, catalytic, diastereo- and enantioselective conjugate addition of N-(diphenylmethylene)glycine tert-butyl ester to β-aryl substituted enones was realized in the presence of 1 mol% of newly desired dinuclear N-spiro-ammonium salts, affording functionalized α-amino acid derivatives in 57-98% yields with high diastereoselectivity (up to 99:1 dr) and enantioselectivity (up to 96.5:3.5 ...
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An efficient highly diastereo- and enantioselective direct Michael addition of nitroalkanes to nitroalkenes catalyzed by chiral squaramide catalyst has been developed. This organocatalytic reaction with a low catalyst loading (2 mol%) proceeded well to afford synthetically useful 1,3-dinitro compounds in high yields with high diastereoselectivities (up to 95 : 5 dr) and excellent enantioselecti...
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ژورنال
عنوان ژورنال: Journal of the American Chemical Society
سال: 2008
ISSN: 0002-7863,1520-5126
DOI: 10.1021/ja710521m