Disclosed are processes for making 2, 3 disubstituted indole compounds such as compounds of general formula I comprised of the steps of
a) reacting a bromoindole compound (i) with a dialkoxyl C
1-5
borane in the presence of a ligand, a palladium catalyst and a base to make a compound of general formula (ii); or alternatively reacting compound (i) with a trialkyl magnesiate reagent, followed by treatment with a borate;
b) reacting the product of step a with a R2-Hal where R2-Hal is defined herein.
Disclosed are 2-bromoaniline or 2-chloroaniline compounds of formula (I):
wherein R, R1 and X are as defined. The compounds are useful as intermediates for preparing indole compounds.
Preparation of 3-substituted-2-pyridin-2-ylindoles: regioselectivity of Larock’s indole annulation with 2-alkynylpyridines
作者:Frank Roschangar、Jianxiu Liu、Emilie Estanove、Marine Dufour、Sonia Rodríguez、Vittorio Farina、Eugene Hickey、Azad Hossain、Paul-James Jones、Heewon Lee、Bruce Z. Lu、Richard Varsolona、Jürgen Schröder、Pierre Beaulieu、James Gillard、Chris H. Senanayake
DOI:10.1016/j.tetlet.2007.11.040
日期:2008.1
A regioselective Larock approach to 3-substituted-2-pyridin-2-ylindoles from 2-alkynylpyridines and 2-iodoanilines is described herein. The unexpectedly high regioselectivity can be rationalized by a combination of steric, coordinative and electronic effects. (C) 2007 Elsevier Ltd. All rights reserved.
PALLADIUM CATALYZED INDOLIZATION OF 2-BROMO OR CHLOROANILINES