Expeditious diastereoselective construction of a thiochroman skeleton via a cinchona alkaloid-derived catalyst
作者:Zhiyun Du、Chenggang Zhou、Yaojun Gao、Qiao Ren、Kun Zhang、Hansong Cheng、Wei Wang、Jian Wang
DOI:10.1039/c1ob06497e
日期:——
diastereoselective and enantioselectivesynthesis of thiochroman derivatives through a sulfa-Michael–Michael cascadesequence is disclosed. This is a significant complement of the quinine-thiourea catalyzed sulfa-Michael–Michael cascade reaction. The denselyfunctionalized target thiochromans were obtained in high diastereoselectivities, and with high to excellent enantioselectivities.
Carbene-Catalyzed Reductive Coupling of Nitrobenzyl Bromide and Nitroalkene via the Single-Electron-Transfer (SET) Process and Formal 1,4-Addition
作者:Yuhuang Wang、Yu Du、Xuan Huang、Xingxing Wu、Yuexia Zhang、Song Yang、Yonggui Robin Chi
DOI:10.1021/acs.orglett.6b03792
日期:2017.2.3
A carbene-catalyzed reductive 1,4-addition of nitrobenzyl bromides to nitroalkenes is disclosed. The reaction proceeds via a carbene-enabled single-electron-transfer process that generates radicals as key intermediates. The present study expands the potentials of carbene catalysis and offers unusual transformations for common substrates in organic synthesis.