Asymmetric Transfer Hydrogenation of N-Unprotected Indoles with Ammonia Borane
作者:Weiwei Zhao、Zijia Zhang、Xiangqing Feng、Jing Yang、Haifeng Du
DOI:10.1021/acs.orglett.0c01930
日期:2020.8.7
A metal-free asymmetric transfer hydrogenation of unprotected indoles was successfully realized using a catalyst derived from HB(C6F5)2 and (S)-tert-butylsulfinamide with ammonia borane as a hydrogen source. A variety of indolines were achieved in 40–78% yields with up to 90% ee.
使用衍生自HB(C 6 F 5)2和(S)-叔丁基亚磺酰胺的氨硼烷作为氢源,成功实现了未保护的吲哚的无金属不对称转移氢化。各种二氢吲哚的收率为40-78%,ee高达90%。
Asymmetric Synthesis of (<i>S</i>)-4,5-Difluoro-2-Methylindoline
作者:Koichi Tsuji、Hiroshi Ishikawa
DOI:10.1080/00397919408010615
日期:1994.11
(S)-4,5-Difluoro-2-methylindoline (S)-11 was synthesized effectively by asymmetric reduction of N-[(R)-N-p-tolylsulfonyl]prolinyl-2-(2-oxo)propyl-3,4-difluoroaniilide 4b followed by successive methylsulfonylation and intra-molecular cyclization.