A New Organocatalyst for the anti-Selective Mannich Reaction

Significance

A new anti-selective catalyst for the Mannich reaction has been developed based on the previously reported C ₂-symmetric pyrrolidine catalyst by Maruoka and co-workers (Tetrahedron Lett. 2006, 47, 8467). Several pyrrolidine 3-sulfonamides have been tested. Catalyst 1 achieves high yields, excellent anti-selectivities, and exceptionally high enantioselectivities. This catalyst is suitable for a broad range of linear and branched aldehydes and ketones. Moreover, a direct three-component reaction involving glyoxaldehyde, 4-methoxy­aniline and butanal is presented, giving comparable results to the Mannich reaction of the preformed imine.