Copper Dithiol Complex Supported on Silica Nanoparticles: A Sustainable, Efficient, and Eco-friendly Catalyst for Multicomponent Click Reaction

Silica-nanoparticle-supported copper-containing ionic liquid (SNIL-Cu­(II)) provided a highly stable, active, reusable, spherical, and solid-phase catalyst for click chemistry. The SNIL-Cu­(II) catalyst was readily prepared from 1,2-bis(4-pyridylthio)­ethane immobilized on silica nanoparticles modified with 3-chloropropyltrimethoxysilane and Cu­(OTf)2, and the morphology, structure, and properties of nanoparticles were investigated through different analytical tools. This catalytic system showed high activity in a one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles by click reactions between a variety of alkynes, organic halides, and sodium azide at room temperature in aqueous polyethylene glycol as a green medium with a high turnover frequency (up to 7920 h–1). Moreover, the SNIL-Cu­(II) was also used as an efficient catalyst for the preparation of a series of multifold 1,4-disubstituted 1,2,3-triazoles. Also, this unique catalyst was readily reused without any decrease in its catalytic activity to give the corresponding triazoles quantitatively.