Click chemistry from organic halides, diazonium salts and anilines in water catalysed by copper nanoparticles on activated carbon

An easy-to-prepare, reusable and versatile catalyst consisting of oxidised copper nanoparticles on activated carbon has been fully characterised and found to effectively promote the multicomponent synthesis of 1,2,3-triazoles from organic halides, diazonium salts, and aromatic amines in water at a low copper loading.