Copper Nanoparticles in Multicomponent and Coupling Reactions

MARÍA JOSE ALBALADEJO; FRANCISCO ALONSO; YANINA MOGLIE; GABRIEL RADIVOY; MIGUEL YUS

Donostía, San Sebastián

Congreso; XXXIV Reunión Bienal de Química Orgánica; 2012

Real Sociedad Española de Química

A versatile catalyst consisting of oxidised copper nanoparticles on activated carbon has been fully characterised and found to promote the multicomponent synthesis of 1,2,3-triazoles from organic halides, diazonium salts, aromatic amines, and epoxides in water. When the copper nanoparticles are supported on titania, the oxidative homocoupling of terminal alkynes is effectively catalysed in the presence of piperidine as a base, in THF or under solvent-free conditions. The latter catalyst has also been shown to catalyse the multicomponent synthesis of propargylamines from aldehydes, amines, and alkynes (A3 coupling) at 70 ºC under solvent-free conditions. All the catalyst are easy to prepare, stable, reusable at a low copper loading, and exhibit higher catalytic activity than some commercially available copper sources. Some mechanistic aspects of these reactions have been undertaken which unveil the participation of copper(I) acetylides in a heterogeneous process.