We herein report an iodine-mediated formal [2 + 2 + 1] cyclization of methylketones, p-toluenesulfonyl hydrazines, and 1-aminopyridinium iodide for preparation of 4-aryl-NH-1,2,3-triazoles under metal- and azide-free conditions. Notably, this is achieved using p-toluenesulfonyl hydrazines and 1-aminopyridinium iodide as azide surrogates, providing a novel route toNH-1,2,3-triazoles. Furthermore, this
involving [3+2] cycloaddition, 1,2-acyl migration and hydrolysis produces 2H-1,2,3-triazoles via the regioselective formation of N2-carboxyalkylated triazoles. The reaction proceeds in aqueousmedia through intriguing reaction kinetics using a CuI–prolinamide catalyst system. Prolinamide promotes the novel organocatalytic 1,2-acyl migration as well as hydrolysis of the resulting N2-carboxyalkylated triazoles
Copper-Catalyzed Synthesis of 4-Aryl-1H-1,2,3-triazoles from 1,1-Dibromoalkenes and Sodium Azide
作者:Xiaokun Wang、Chunxiang Kuang、Qing Yang
DOI:10.1002/ejoc.201101204
日期:2012.1
A new methodology for the Cu-catalyzed synthesis of 1H-1,2,3-triazoles from1,1-dibromoalkenes and sodiumazide is presented. Aryl dibromoolefins were efficiently converted into the corresponding 1,2,3-triazoles. A comprehensive number of functional groups were compatible with this reaction. 1,2,3-Triazoles were obtained in moderate to excellent yields.
The copper(I)-catalyzed azide–alkyne cycloaddition reaction has been extensively studied and widely applied in organic synthesis. However, the formation of 1,2,3-triazoles with electron-deficient azide has been a challenging problem. In this report, we have demonstrated the formation of regioselective 1,4-disubstituted 1,2,3-triazoles from various types of aryl terminal alkynes and azidoformates, which
Compounds of this invention are non-peptide, reversible inhibitors of type 2 methionine aminopeptidase, useful in treating conditions mediated by angiogenesis, such as cancer, haemangioma, proliferative retinophathy, rheumatoid arthritis, atherosclerotic neovascularization, psoriasis, ocular neovascularization and obesity.