Synthesis of chiral sulfoximine-based thioureas and their application in asymmetric organocatalysis

Abstract

For the first time, chiral sulfoximine derivatives have been applied as asymmetric organocatalysts. In combination with a thioureatype backbone the sulfonimidoyl moiety leads to organocatalysts showing good reactivity in the catalytic desymmetrization of a cyclic meso-anhydride and moderate enantioselectivity in the catalytic asymmetric Biginelli reaction. Straightforward synthetic routes provide the newly designed thiourea-sulfoximine catalysts in high overall yields without affecting the stereohomogeneity of the sulfur-containing core fragment. © 2012 Frings et al.