Enantioselective Catalysis of the Aza-Cope Rearrangement by a Chiral Supramolecular Assembly

Journal Article · Wed Jul 29 04:00:00 EDT 2009 · Journal of the American Chemical Society

DOI:https://doi.org/10.1021/ja906386w· OSTI ID:993492

Brown, Casey J; Bergman, Robert G; Raymond, Kenneth N

The chiral supramolecular catalyst Ga{sub 4}L{sub 6} [L = 1,5-bis(2,3-dihydroxybenzoylamino)naphthalene] is a molecular tetrahedron that catalyzes the 3-aza-Cope rearrangement of allyl enammonium cations. This catalysis is accomplished by preorganizing the substrate in a reactive conformation within the host. This work demonstrates that through the use of enantiopure assembly, its chiral cavity is capable of catalyzing the 3-aza-Cope rearrangement enantioselectively, with yields of 21-74% and enantiomeric excesses from 6 to 64% at 50 C. At lower temperatures, the enantioselectivity improved, reaching 78% ee at 5 C. This is the highest enantioselectivity to date induced by the chiral cavity of a supramolecular assembly.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: Chemical Sciences Division
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 993492
• Report Number(s): LBNL-2886E
• Journal Information: Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 48 Vol. 131; ISSN 0002-7863; ISSN 1520-5126
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATALYSIS
CATALYSTS
CATIONS
SUBSTRATES