Efficient One-Pot Copper(I)-Catalyzed Azide-Alkyne Cycloaddition in Water: Triazole Synthesis, Catalytic Applications, DFT Studies, and Biological Evaluation.

A series of Cu-N-heterocyclic carbene (Cu-NHC) complexes (3a-e) was successfully synthesized and their structures verified by NMR, HRMS, and elemental analysis. These complexes displayed excellent catalytic performance in the 1,3-dipolar cycloaddition of alkynes with azides, producing 1,4-disubstituted triazoles (4a-e) in isolated yields of 80%-91%. The cycloaddition between phenylacetylene and various azides was also explored theoretically using DFT/B3LYP/6-311+G(d) methods. The cytotoxic properties of the obtained compounds were evaluated against A549, HCT116, and BEAS-2B cell lines, with several derivatives exhibiting significant anticancer activity. Moreover, their antioxidant potential was assessed through DPPH and ABTS radical-scavenging assays, in which compound 2 showed particularly strong performance.