Intra- and Intermolecular Reactions of Indoles with Alkynes Catalyzed by Gold
作者:Catalina Ferrer、Catelijne H. M. Amijs、Antonio M. Echavarren
DOI:10.1002/chem.200601324
日期:2007.2.2
Indoles react intramolecularly with alkynes in the presence of gold catalysts to give fromsix- to eight-membered-ring annulated compounds. The cationic Au(I) complex [Au(PC(6)H(4)(o-Ph)}(tBu)(2))(NCMe)]SbF(6) is the best catalyst for the formation of six- and seven-membered rings by 6-endo-dig, 6-exo-dig, and 7-exo-dig cyclizations. Indoloazocines are selectively obtained with AuCl(3) as catalyst
Enantioselective Organocatalytic Indole Alkylations. Design of a New and Highly Effective Chiral Amine for Iminium Catalysis
作者:Joel F. Austin、David W. C. MacMillan
DOI:10.1021/ja017255c
日期:2002.2.1
"privileged" structure with representation in over 3000 natural isolates and 40 medicinal agents of diverse therapeutic action. A newstrategy for asymmetric access to this important pharmacaphore has been accomplished that involves the amine catalyzed alkylation of indoles with alpha,beta-unsaturated aldehydes. Central to these studies has been the design of a newchiral amine catalyst that exhibits
Enantioselective Friedel–Crafts alkylations catalysed by well-defined iridium and rhodium half-sandwich complexes
作者:Daniel Carmona、María Pilar Lamata、Antonio Sánchez、Fernando Viguri、Luis A. Oro
DOI:10.1016/j.tetasy.2011.05.003
日期:2011.4
Aqua-complexes (S-M,R-C)-[C-p*M((R)-prophos)(H2O)][SbF6](2)(M = Rh 1, Ir 2) catalysed the alkylation of alpha,beta-unsaturated aldehydes with aromatics and heteroaromatics but in some cases, mixtures of products were obtained. Complexes 1 and 2 were also used to activate nitroalkenes for the Friedel-Crafts alkylation of a variety of aromatics and heteroaromatics, in particular, 1,3,5-trimethoxybenzene. For this substrate, the monoalkylated adduct was obtained in quantitative yield with enantioselectivities of up to 73% ee being achieved. The intermediate catalyst/nitroalkene was isolated and characterized and the complex catalyst/adduct was detected spectroscopically. From these data a plausible catalytic cycle is proposed. (C) 2011 Elsevier Ltd. All rights reserved.