Dearomatization of tryptophols via a vanadium-catalyzed asymmetric epoxidation and ring-opening cascade
作者:Long Han、Chuan Liu、Wei Zhang、Xiao-Xin Shi、Shu-Li You
DOI:10.1039/c3cc47921h
日期:——
An enantioselective epoxidation of tryptophols followed by an intramolecular epoxide opening reaction was realized by chiral vanadium catalysts derived from C2 symmetric bis-hydroxamic acid (BHA) ligands. 3a-Hydroxyfuroindoline derivatives with up to 89% yield and 90% ee were obtained under mild reaction conditions.
nucleophilic bromination at the C5-position of tryptophol and tryptamine derivatives is difficult and remains unexplored. Herein, we report a tunable water-mediated electrooxidative protocol for the dearomative C3/C5-bromocyclization of tryptophol and tryptamine derivatives. This electrosynthetic approach enables selective construction of cyclic 3a- or 5a-bromoindolines simply by the addition of different