Organocatalytic direct asymmetric Michael reactions of α-aminoaldehyde with β-nitroolefins: Facile synthesis of unnatural β-disubstituted α-aminoacid

ORGN 756

Rajeswari Thayumanavan, trajee@scripps.edu, Fujie Tanaka, and Carlos F. Barbas III. Departments of Chemistry and Molecular Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037
We recently reported the synthesis of highly enantiomerically enriched anti-b-hydroxy – a-aminoacid derivatives by using a-aminoaldehyde as a donor in organocatalytic direct asymmetric aldol reactions. These results encouraged us to investigate a-aminoaldehyde donors in asymmetric direct Michael reactions with b-nitro olefins. We found various chiral diamines catalyze direct Michael reactions of a-aminoaldehyde with various b-nitro olefins in good to moderate diastereoselectivity with excellent enantioselectivities. Resulting Michael adducts were further oxidized to give unnatural b-disubstituted a-aminoacid derivatives.

 

Asymmetric Reactions, Molecular Recognition, Self Assembly, Bioorganic Chemistry, Process R&D
8:00 PM-10:00 PM, Wednesday, 16 March 2005 Convention Center -- Hall D, Poster

Division of Organic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005