Organocatalytic enantioselective one-pot synthesis of β-aminoketones via Mannich reaction

An effective protocol for the asymmetric synthesis of β-amino carbonyl compounds using pyrrolidine based organocatalyst has been developed via one-pot three-component Mannich reaction. The organocatalyst (S)-N-(2,4-dinitrophenyl) pyrrolidine-2-carboxamide 3b confirmed to be the superior organocatalyst in solvent acetonitrile to obtain corresponding products in up to 89% yield and with excellent ee (90%). This organocatalytic reaction reveals productive result with a range of other aldehydes. Aromatic aldehydes having electron withdrawing substituent show the best results. Excellent yields, high enantioselectivity, mild reaction condition, and simple experimental work-up procedure are some of the advantages of this method.

Keywords:

Mannich reaction , Organocatalyst , β-amino carbonyl compounds Enantioselectivity , Multicomponent reaction