Cobalt-Catalyzed Reductive Multicomponent Synthesis of β-Hydroxy- and β-Aminocarbonyl Compounds under Mild Conditions

The cobalt-catalyzed multicomponent reaction between sp² -hybridized organic halides, Michael acceptors, and unsaturated electrophiles has been developed. The reaction proceeds through a formal conjugate addition/aldol or aza-aldol (Mannich) tandem reaction initiated by the in situ metalation of the organic halide by cobalt catalysis. The essentially new reaction conditions that have been developed are very mild and atom-economic. Under these conditions, a broad range of β-hydroxy- and β-aminocarbonyl compounds are obtained in good to high yields.