1,3‐Dipolar Cycloaddition of Alkanone Enolates with Azides in Deep Eutectic Solvents for the Metal‐Free Regioselective Synthesis of Densely Functionalized 1,2,3‐Triazoles

An eco-friendly metal-free protocol was developed for the regioselective synthesis of densely functionalized 1,2,3-triazoles through a 1,3-dipolar cycloaddition reaction alkanone enolates with azides performed in environmentally responsible choline chloride/urea or acetate/urea eutectic mixture. This approach displays broad substrate scope, straightforwardly furnishing desired triazoles (including challenging phenolic derivatives) yields up to 98 %, while working at room temperature and under aerobic conditions. The practicability method is exemplified by sustainable some pharmaceutically relevant triazole derivatives carried out via telescoped, one-pot cycloaddition/reduction processes same mixture without any halfway isolation/purification step intermediates.