A Novel Bifunctional Sulfonamide Primary Amine-Catalyzed Enantioselective Conjugate Addition of Ketones to Nitroolefins
作者:Fei Xue、Shilei Zhang、Wenhu Duan、Wei Wang
DOI:10.1002/adsc.200800445
日期:2008.10.6
The enantioselectiveconjugateaddition of a variety of ketones to nitroolefins has been developed. The process is efficiently catalyzed by a novelbifunctionalsulfonamideprimary amine in good yields and with good levels of enantioselectivity.
Based on different chiral diamine skeletons, a series of bifunctional primary amine-thiophosphoramides were synthesized and screened as the catalysts for the asymmetric Michael addition of acetone to both aromatic and aliphatic nitroolefins. Under the catalysis of a thiophosphoramide derived from 1,2-diphenylethane-1,2-diamine, the corresponding adducts were obtained in high yields (up to >99%) with
A series of bifunctional primary amine-thiophosphoramides were synthesized, which proven to be effective organocatalysts for the asymmetric Michael reaction of acetone to both aryl and alkyl nitro olefins in the presence of phenol as a protic additive. The corresponding adducts were obtained in excellent chemical yields (up to >99 %) with excellent enantioselectivities (up to 97 % ee).
Simple Cyclohexanediamine-Derived Primary Amine Thiourea Catalyzed Highly Enantioselective Conjugate Addition of Nitroalkanes to Enones
作者:Kui Mei、Mei Jin、Shilei Zhang、Ping Li、Wenjing Liu、Xiaobei Chen、Fei Xue、Wenhu Duan、Wei Wang
DOI:10.1021/ol9010322
日期:2009.7.2
A highly enantioselective conjugate addition of nitroalkanes to enones has been developed. The process is efficiently catalyzed by a simple chiral cyclohexanediamine-derived primary amine thiourea with a broad substrate scope.