RESUMO
The chemoselective functionalization of a range of dihaloaromatics with methyl, cyclopropyl, and higher alkyl Grignard reagents via iron-catalyzed cross-coupling is described. The site selectivity of C-X (X = halogen) activation is determined by factors such as the position of the halogen on the ring, the solvent, and the nucleophile. A one-pot protocol for the chemoselective synthesis of mixed dialkyl heterocycles is achieved solely employing iron catalysis.
Assuntos
Alcanos/química , Reagentes de Ligações Cruzadas/química , Halogênios/química , Hidrocarbonetos Halogenados/química , Ferro/química , Catálise , Estrutura MolecularRESUMO
Nitroalkenes readily undergo palladium-catalyzed [3 + 2] cycloaddition with trimethylenemethane to generate nitrocyclopentanes in excellent yield and enantioselectivity. Furthermore, the products thus formed are highly versatile synthetic intermediates and provide convenient access to both cyclopentylamines and cyclopentenones.
Assuntos
Alcenos/química , Metano/análogos & derivados , Nitrogênio/química , Paládio/química , Catálise , Ciclização , Ligantes , Metano/química , Modelos Moleculares , Estrutura Molecular , EstereoisomerismoRESUMO
A general method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazoles has been developed from reaction of carboxylic acids, primary amidines, and monosubstituted hydrazines. This highly regioselective and one-pot process provides rapid access to highly diverse triazoles.