US Patent 7763736 Copper-catalysed ligation of azides and acetylenes

A copper catalyzed click chemistry ligation process is employed to bind azides and terminal acetylenes to provide 1,4-disubstituted 1,2,3-triazole triazoles. The process comprises contacting an organic azide and a terminal alkyne with a source of reactive Cu(I) ion for a time sufficient to form by cycloaddition a 1,4-disubstituted 1,2,3-triazole. The source of reactive Cu(I) ion can be, for example, a Cu(I) salt or copper metal. The process is preferably carried out in a solvent, such as an aqueous alcohol. Optionally, the process can be performed in a solvent that comprises a ligand for Cu(I) and an amine.