Three-Component Coupling of Aldehydes, Amines, and Alkynes Catalyzed by Oxidized Copper Nanoparticles on Titania

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

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2012 p. 3093 - 3104

1434-193X

Copper nanoparticles (mainly as Cu2O) on titania have been shown to catalyze the multicomponent synthesis of propargylamines from aldehydes, amines, and alkynes (A3 coupling) effectively at 70 °C under solvent-free conditions. Both aromatic and aliphatic aldehydes and alkynes have been combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields. Two exam ples of ketone/amine/alkyne (KA2) coupling are also included. The catalyst is easy to prepare, reusable at a low copper loading (0.5 mol-%), and exhibits higher catalytic activity than some commercially available copper sources. Some mechanistic aspects of the reaction have also been examined, which have unveiled the participation of copper(I) acetylides in a heterogeneous process