A stereocontrolledtotalsynthesis of (+)-vinblastine was accomplished, featuring preparations of the two indole units by means of a novel indole synthesis via radical cyclization of thioanilide, and a stereoselective coupling of these units.
Radical Cyclization of 2-Alkenylthioanilides: A Novel Synthesis of 2,3-Disubstituted Indoles
作者:Hidetoshi Tokuyama、Tohru Yamashita、Matthew T. Reding、Yosuke Kaburagi、Tohru Fukuyama
DOI:10.1021/ja983681v
日期:1999.4.1
Lewis Base–Boryl Radicals Enabled the Desulfurizative Reduction and Annulation of Thioamides
作者:You-Jie Yu、Feng-Lian Zhang、Jie Cheng、Jing-Hao Hei、Wei-Ting Deng、Yi-Feng Wang
DOI:10.1021/acs.orglett.7b03201
日期:2018.1.5
A new protocol for radical transformations of thioamides promoted by Lewis base-boryl radicals is reported. The desulfurizative reduction to access organic amines was enabled utilizing 4-dimethylaminopyridine-BH3 as the boryl radical precursor and PhSH as the polarity reversal catalyst. Alternatively, the chain process for unsaturated thioamides was switched to an annulation reaction using N-heterocyclic carbene BH3 as the boryl radical precursor and sterically bulky Ph3CSH as the catalyst, allowing for the construction of N-heterocyclic and carbocyclic skeletons.