Direct Access To 1,2,4-triazoles Via Copper-catalyzed Diamination Of Arylnitriles

We have summarized synthetic approaches involving triazoles and their various derivatives. In addition, we have developed a new efficient and regioselective route to 1,3,5-trisubstituted-1H-1,2,4-triazoles. The access by way of copper catalyzed tandem addition/oxidative cyclization employs N-phenylbenzamidines and nitriles as substrates. The reaction with facile conditions tolerates a broad range of functional groups and is directional for future similar attempts.The article contains two chapters.Chapter One is a synthetic chemistry review of triazoles and their derivatives. Basically, triazoles are divided into two species: 1,2,3-triazoles and 1,2,4-triazoles. Earlier synthetic methods for 1,2,3-triazoles included Huisgen cycloaddition, which were then superseded by copper-catalyzed azide-alkyne cycloaddition(CuAAC) as well as ruthenium-catalyzed azide-alkyne cycloaddition(RuAAC) with opposite regioselective products. Einhorn-Brunner reaction and Pellizzari reaction were pioneering efforts on 1,2,4-triazoles’ synthesis using different reactants; while later tactics largely lifted numerous limits in terms of reaction conditions.Chapter Two is an overview of prior attempts on copper-catalyzed oxidative cyclization/tandem reaction presented by our group as well as the main experimental section on copper-catalyzed diamination of arylnitriles from N-phenylbenzamidines. The experimental section starts with the synthetic method of N-phenylbenzamidines and their derivatives. The next procedure is the optimization of reaction conditions with subsequent approaches concerning an extension of substrates’ species. We have also explored the reaction mechanism. Lastly, we have provided particular physical properties, NMR/HRMS parameters as well as NMR spectra of certain triazole products.