Cu2O/CuO@mont K 10 promoted one-pot synthesis of 1,2,3-triazoles through azide-alkyne cycloaddition reaction

A Cu2O/CuO@mont K 10 nano hybrid material has been synthesized following a biogenic method using aqueous green leaf extract of Tulsi (Ocimum sanctum) as a reducing/stabilizing agent. The bulkier organic constituents of the leaf such as alkaloids, terpenoids, polyphenols, etc. support the nanoparticles on the mont K10 clay matrix. The fabricated nano architecture was characterized by SEM, TEM, SEM-EDX, powder XRD, XPS, ICP-AES analysis, and BET surface area measurements. X-ray photoelectron spectroscopy study of the synthesized material showed the co-existence of Cu (I) as a major species along with Cu (II) species in small quantities in the clay matrix. BET analysis showed that after insertion of Cu2O and CuO nanoparticles into Mont K 10, the surface area and pore volume of Cu2O/CuO@mont K 10 nano hybrid became 112.0 m(2)g(-1) and 0.209 cm(3)g(-1), respectively. These values are smaller compared to bare clay matrix, substantiating the successful deposition of Cu2O and CuO nanoparticles in the matrix. The fabricated nanomaterial Cu2O/CuO@mont K 10 exhibited surprising catalytic activity towards the "click" azide-alkyne cycloaddition reaction for the regioselective synthesis of 1, 2, 3-Triazole. The reaction proceeds through a one-pot procedure via a three-component reaction among alkyl halide, sodium azide, and a terminal alkyne in water under open-air conditions. The protocol offers a simple way to access a wide range of triazoles containing both aliphatic and aromatic counterparts with good to excellent isolated yield (75-98%). The catalyst is truly heterogeneous, recoverable, and reusable up five times without compromising the catalytic efficiency, suggesting a future potential of the mesoporous catalytic system.