Ruthenium-Catalyzed Regioselective C–H Bond Acetoxylation on Carbazole and Indole Frameworks
摘要:
The regioselective C-H bond cleavage/C-O bond formation takes place smoothly upon treatment of 9-(pyridin-2-yl)carbazoles with acetic acid in the presence of a silver salt oxidant under ruthenium catalysis to afford the corresponding Cl- and C8-diacetoxylated products. Under similar conditions, the acetoxylation of 2-aryl-1-(pyridin-2-yl)indoles as well as 1-aryl-7-azaindoles can also be conducted efficiently.
readily available N-(2-pyridyl)anilines and commercially available α-Cl ketones through iridium-catalyzed C–H activation and cyclization is reported here. As a complementary approach to the conventional strategies for indole synthesis, the transformation exhibits powerful reactivity, tolerates a large number of functional groups, and proceeds with good to excellent yields undermildconditions, providing
Ruthenium-Catalyzed Direct C–H Bond Arylations of Heteroarenes
作者:Lutz Ackermann、Alexander V. Lygin
DOI:10.1021/ol2010648
日期:2011.7.1
Ruthenium-catalyzedC–Hbondarylations of indoles, thiophenes, and pyrroles were accomplished in a highly chemo- and site-selective manner through the use of removable directing groups.
Indole is a ubiquitous structural motif with important applications in many areas of chemistry. Given this, a simple and efficient Ru(II)-catalyzed synthesis of indole via intermolecular annulation of N-aryl-2-aminopyridines and sulfoxonium ylides was proposed and accomplished. Excellent selectivity and good functional group tolerance of this transformation were observed. This protocol provides easy
A highly regioselective synthesis of 2-substituted indoles was realized through Ir(III)-catalyzed CH functionalization of N-phenylpyridin-2-amines followed by the reaction with sulfoxonium ylides and intramolecular cyclization under mild conditions. The reaction completed with broad range of substrate scopes and gave various 2-substituted indoles in up to 98% yields.
Cobalt-Catalyzed CH Bond Functionalizations with Aryl and Alkyl Chlorides
作者:Benudhar Punji、Weifeng Song、Grigory A. Shevchenko、Lutz Ackermann
DOI:10.1002/chem.201301409
日期:2013.8.5
catalytic CH bond arylations on heteroaryl‐substituted arenes with widely available aryl chlorides, which set the stage for the preparation of sterically hindered tri‐ortho‐substituted biaryls. Likewise, challenging direct alkylations with β‐hydrogen‐containing primary and even secondary alkyl chlorides proceeded on pyridyl‐ and pyrimidyl‐substituted arenes and heteroarenes. The cobalt‐catalyzed CH bond