An Ionic Liquid Containing L-Proline Moiety as Highly Efficient and Recyclable Chiral Organocatalyst for Michael Addition
作者:Jiang Li、Xia Bing Li、Sha Sha Ma、Juan Liu、Ben Hao Li、Bao Lin Li
DOI:10.1002/bkcs.10848
日期:2016.8
A novel chiral ionic liquid containing proline moiety was synthesized. It can be used as a highlyefficient and recyclable chiral organocatalyst for Michaeladdition of cyclohexanone with (E)‐β‐nitroalkenes in methanol at room temperature. The Michaeladdition affords the corresponding products in satisfactory yields of isolated products (78–98%) with high diastereoselectivities and excellent enantioselectivities
4-Trifluoromethanesulfonamidyl prolinol tert-butyldiphenylsilyl ether as a highly efficient bifunctional organocatalyst for Michael addition of ketones and aldehydes to nitroolefins
作者:Chao Wang、Chun Yu、Changlu Liu、Yungui Peng
DOI:10.1016/j.tetlet.2009.02.211
日期:2009.5
4-Trifluoromethanesulfonamidyl prolinol tert-butyldiphenylsilyl ether bifunctionalorganocatalyst 3a is a highly efficient catalyst for the asymmetric Michaeladdition reactions of ketones and aldehydes to nitrostyrenes, leading to syn-selective adducts with excellent yields (>99%), high diastereoselectivities (up to 99:1 dr) and excellent enantioselectivities (up to 99% ee). Control experiments suggested that the
Highly enantioselective Michael addition reactions in water catalyzed by an insoluble MPS-supported 4-sulfonamidyl prolinol tert-butyldiphenylsilyl ether
作者:Yongming Chuan、Guihua Chen、Yungui Peng
DOI:10.1016/j.tetlet.2009.04.011
日期:2009.6
The development of a highly efficient, insoluble, and non-swelling MPS-supported organocatalyst for the direct asymmetric Michael reaction of ketones and aldehydes to nitrostyrenes at room temperature in water is described. Excellent yields (up to 100%) and high stereoselectivities (up to 94% dr and 93% ee) were achieved with 10 mol % of the catalyst. The resin-bound catalyst was simply separated and
Organocatalysis with proline derivatives: improved catalysts for the asymmetric Mannich, nitro-Michael and aldol reactions
作者:Alexander J. A. Cobb、David M. Shaw、Deborah A. Longbottom、Johan B. Gold、Steven V. Ley
DOI:10.1039/b414742a
日期:——
Tetrazole and acylsulfonamide organocatalysts derived from proline have been synthesised and applied to the asymmetric Mannich, nitro-Michael and aldol reactions to give results that are superior to the proline-catalysed counterpart.
Novelbifunctionalchiralsquaramide–amine organocatalysts have been developed by rational combination of pyrrolidine and a cinchona alkaloid. The catalysts promoted the enantioselective Michael addition of both mono- and diketones to a broad range of nitroalkenes providing the corresponding products in moderate to high yields with excellent enantioselectivities and diastereoselectivities (up to 96%