Ruthenium Hydride/Brønsted Acid-Catalyzed Tandem Isomerization/<i>N</i>-Acyliminium Cyclization Sequence for the Synthesis of Tetrahydro-β-carbolines
作者:Casper L. Hansen、Janie W. Clausen、Ragnhild G. Ohm、Erhad Ascic、Sebastian T. Le Quement、David Tanner、Thomas E. Nielsen
DOI:10.1021/jo402192s
日期:2013.12.20
reaction but also attractive possibilities for total synthesis, including rapid generation of molecular complexity and formation of quaternary stereogenic centers. TBHCs can also be accessed by harnessing the Suzuki cross-coupling reaction to the isomerization/N-acyliminiumcyclizationsequence. Finally, diastereo- and enantioselective versions of the title reaction have been examined using substrate control
Oxidative rearrangement of indoles is an essential transformation that has been widely used in the synthesis of many pharmaceutical agents and bioactive natural products. Herein, we report an efficient, practical and metal-free method for the oxidative rearrangement of indoles to spirooxindoles, 2-oxindoles, 2,2-disubstituted indolin-3-ones, and oxa-spirooxindoles using 10 mol% HBr and hydrogen peroxide