Tandem conjugate addition–elimination reaction promoted by chiral pyrrolidinyl sulfonamide (CPS)
作者:Junye Xu、Xiao Fu、Ruijuan Low、Yong-Peng Goh、Zhiyong Jiang、Choon-Hong Tan
DOI:10.1039/b810905m
日期:——
Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate additionâelimination reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.
Synthesis of α-Stereogenic Amides and Ketones by Enantioselective Conjugate Addition of 1,4-Dicarbonyl But-2-enes
作者:Zhiyong Jiang、Yuanyong Yang、Yuanhang Pan、Yujun Zhao、Hongjun Liu、Choon-Hong Tan
DOI:10.1002/chem.200802601
日期:2009.5.4
Constructing α‐stereogenic amides and ketones: The highly regioselective and enantioselectiveconjugateaddition of 1,3‐dicarbonyl compounds to 1,4‐dicarbonyl but‐2‐enes has been developed with the chiral bicyclic guanidine as catalyst (ee values up to 97 %; see scheme).
Chiral Bicyclic Guanidine as a Versatile Brønsted Base Catalyst for the Enantioselective Michael Reactions of Dithiomalonates and β-Keto Thioesters
作者:Weiping Ye、Zhiyong Jiang、Yujun Zhao、Serena Li Min Goh、Dasheng Leow、Ying-Teck Soh、Choon-Hong Tan
DOI:10.1002/adsc.200700326
日期:2007.11.5
A chiral bicyclic guanidine was developed as a versatile Brønsted base catalyst for the enantioselective Michael reactions of dithiomalonates and β-keto thioesters using a range of acceptors including maleimides, cyclic enones, furanone and acyclic 1,4-dicarbonylbutenes.