A base-modulated chemoselective synthesis of 3-cyanoindoles or 4-cyanoquinolines using a palladium-catalyzed N-heterocyclization
摘要:
A selective methodology for the synthesis of either 3-cyanoindoles or 4-cyanoquinolines via a base-modulated palladium-catalyzed reductive N-heterocyclization from a common 1-cyano-1-(2-nitrophenyl)-1-alkene precursor is described. The required starting materials were prepared either by a Kosugi Migita Stille coupling of 2-halo-1-nitrobenzenes with a tributyl(1-alkenyl)stannane or by a vicarious nucleophilic substitution (VNS) of nitrobenzenes followed by a Knoevenagel condensation with an aldehyde. (C) 2011 Elsevier Ltd. All rights reserved.
A base-mediated synthesis of N-hydroxy- and N-alkoxyindoles from 2-nitrostyrenes
作者:Blaine T. McClay、Katharine E. Lambson、Serge R. Banini、Tural N. Akhmedov、Björn C.G. Söderberg
DOI:10.1016/j.tet.2023.133578
日期:2023.9
2-(2-nitroaryl)-2-butenoates with potassium tert-butoxide and an electrophile, such as methyl iodide, benzyl bromide and allyl bromide, afforded N-alkoxyindoles. In related reactions, using sodium tert-pentoxide as the base with or without in situ addition of an electrophile afforded N-alkoxy- and N-hydroxyindoles, respectively. Electrophiles such as dimethylsulfate, p-tosyl chloride, and acetic anhydride afforded