PDF herunterladen
Synfacts 2009(6): 0674-0674  
DOI: 10.1055/s-0029-1216774
Organo- and Biocatalysis
© Georg Thieme Verlag Stuttgart ˙ New York

A New Pyrrolidine-Based Catalyst for Nitro-Michael Additions

Contributor(s): Benjamin List, Corinna Reisinger
B. Tan, X. Zeng, Y. Lu, P. J. Chua, G. Zhong*
Nanyang Technological University, republic of Singapore
Weitere Informationen

Publikationsverlauf

Publikationsdatum:
25. Mai 2009 (online)

    Lizenzen und Reprints

Significance

Zhong and co-workers report the application of the new pyrrolidine-based organocatalyst 3 in the asymmetric Michael addition of six-membered cyclic ketones 1 to (hetero)aromatic nitroolefins 2 giving the corresponding Michael adducts 4 in high yields (87-99%) along with excellent diastereo- and enantioselectivities (98:2 to >99:1 dr, 96:4 to >99.5:0.5 er). The strong polar P=O group of catalyst 3 is attributed to play a ­significant role. As supported by DFT calculations, it likely orientates the nitro group for the stereo­selective enamine addition via a strong H-bond mediated by water.