A highly efficient strategy for the kinetic resolution of Michael adducts was realized using a chiral N‐heterocyclic carbene catalyst. The kinetic resolution provides a new convenient route to single diastereomers of cyclohexenes and Michael adducts in good yields with high enantiomeric excesses (up to 99 % ee with a selectivity factor of up to 458). This “two flies with one swat” concept allows the
Squaramide-catalyzed enantioselective Michael addition of malononitrile to chalcones
作者:Wen Yang、Yang Jia、Da-Ming Du
DOI:10.1039/c1ob06302b
日期:——
A highlyenantioselective Michael addition of malononitrile to chalconescatalyzed by a chiral quinine-derived squaramide catalyst has been developed. This organocatalytic reaction at a very lowcatalystloading (0.5 mol%) led to chiral γ-cyano carbonyl compounds in good yields with high enantioselectivities (up to 96% ee) under mild reaction conditions.
Chloramphenicol base chemistry. Part 11: 1 chloramphenicol base-derived thiourea-catalyzed enantioselective Michael addition of malononitrile to α , β -unsaturated ketones
The first chloramphenicol base-derived thiourea-catalyzed enantioselective Michael addition of malononitrile to alpha,beta-unsaturated ketones is reported. The Michael adducts were obtained in good to excellent yields (up to 98% yield) and enantioselectivities (up to 94% ee). This reaction has a broad substrate scope to various alpha,beta-unsaturated ketones. With this in mind, this methodology was successfully applied to the synthesis of a chiral piperidone, an advanced building block for dihydropyridinone P2X(7) receptor antagonists. (C) 2017 Published by Elsevier Ltd.
Organocatalytic asymmetric direct Michael addition of aromatic ketones to alkylidenemalononitriles
作者:Lei Yue、Wei Du、Yan-Kai Liu、Ying-Chun Chen
DOI:10.1016/j.tetlet.2008.04.069
日期:2008.6
The asymmetric direct Michael addition of aromatic ketones to highly active alkylidenemalononitriles was investigated by employing a chiral primary amine 9-amino-9-deoxyepicinchonine. In general modest to good enantioselectivities (71-84% ee) could be obtained in acceptable isolated yields (48-85%) for an array of substrates. (c) 2008 Elsevier Ltd. All rights reserved.
Moirangthem, Nimalini; Thingom, Bhavna; Moirangthem, Soniya D, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 2013, vol. 52, # 7, p. 937 - 941
作者:Moirangthem, Nimalini、Thingom, Bhavna、Moirangthem, Soniya D、Laitonjam, Warjeet S