Bifunctional tertiary amine-squaramide catalyzed asymmetric catalytic 1,6-conjugate addition/aromatization of para-quinone methides with oxindoles
作者:Yu-Hua Deng、Xiang-Zhi Zhang、Ke-Yin Yu、Xu Yan、Ji-Yuan Du、Hanmin Huang、Chun-An Fan
DOI:10.1039/c5cc10502a
日期:——
Asymmetric catalytic 1,6-addition of p-QMs with racemic oxindoles under the bifunctionalcatalysis of C2-symmetric dimeric Cinchona-derived squaramides is described. This tertiary amine-squaramide catalzyed reaction provides a diastereoselective and enantioselective approach...
Highly Diastereo- and Enantioselective Michael Additions of 3-Substituted Oxindoles to Maleimides Catalyzed by Chiral Bifunctional Thiourea−Tertiary Amine
A highlydiastereo- and enantioselective Michael addition reaction with respect to prochiral 3-substituted oxindoles and maleimides by a chiral bifunctional thiourea−tertiary amine catalyst was investigated for the first time. The corresponding adducts, containing a quaternary center at the C3-position of the oxindole as well as a vicinal tertiary center, were generally obtained in good to high yields
Enantioselective Michael addition of 3-aryloxindoles to a vinyl bisphosphonate ester catalyzed by a cinchona alkaloid derived thiourea catalyst
作者:Mei-Xin Zhao、Tong-Lei Dai、Ran Liu、Deng-Ke Wei、Hao Zhou、Fei-Hu Ji、Min Shi
DOI:10.1039/c2ob25966d
日期:——
A highly enantioselective Michael addition of 3-aryloxindole to vinyl bisphosphonate ester catalyzed by a cinchonidine derived thiourea catalyst has been investigated. The corresponding adducts, containing a chiral quaternary carbon center and geminal bisphosphonate ester fragment at the 3-position of the oxindole, were obtained in moderate to good yields (65–92%) and moderate to good enantioselectivities
Catalytic Enantioselective Dearomatization/Rearomatization of 2-Nitroindoles to Access 3-Indolyl-3′-Aryl-/Alkyloxindoles: Application in the Formal Synthesis of Cyclotryptamine Alkaloids
作者:Wei-Cheng Yuan、Xiao-Jian Zhou、Jian-Qiang Zhao、Yong-Zheng Chen、Yong You、Zhen-Hua Wang
DOI:10.1021/acs.orglett.0c02350
日期:2020.9.18
The first catalyticenantioselective dearomatization/rearomatization of 2-nitroindoles triggered by the Michael addition of 3-monosubstituted oxindoles was established. A wide range of 3-indolyl-3′-alkyloxindoles (up to 99% yield, 97% ee) and 3-indolyl-3′-aryloxindoles (up to 95% yield, 99% ee) were obtained by using an organocatalyst. This method provides an unprecedented strategy to access structurally