An environmentally friendly protocol for oxidative halocyclization of tryptamine and tryptophol derivatives
作者:Jun Xu、Rongbiao Tong
DOI:10.1039/c7gc01341h
日期:——
environmentally friendly and efficient protocol (KX/oxone) for oxidative halocyclization of tryptamine/tryptophol derivatives was developed and demonstrated with 28 examples and concisetotalsynthesis of cyclotryptamine alkaloid protubonines A and B. The distinct advantage of this protocol over all previous methods is that no organic byproduct is generated from a halogenating agent or oxidant, thus greatly reducing
Highly asymmetric bromocyclization of tryptophol by using chiral anionic phase-transfer catalyst and DABCO-derived brominating reagent is described. Optimization of the reaction conditions revealed that the reaction rate was accelerated together with improvement of enantioselectivity by addition of catalytic DABCO-derived brominating reagent. From tryptophol, 3-bromofuroindoline could be directly obtained in excellent enantioselectivities by employing this novel methodology.