Combining Asymmetric Aminocatalysis with Palladium-Catalyzed Carbon Monoxide Activation
Final Report Abstract
An organocatalytic enantioselective synthesis of tetrahydrofurobenzofuran- and methanobenzodioxepin scaffolds has been developed via two divergent pathways from hydroxyarenes and γ-keto-enals. One reaction path leads to the formation of chiral 5,5-fused tetrahydrofurobenzofuran scaffolds bearing two stereocenters while the other pathway provides 5,6- bridged methanobenzodioxepin scaffolds containing three stereocenters. The obtained products are contained as core structure in natural products like aflatoxins and bullataketals. The tetrahydrofurobenzofurans are formed in moderate yields and up to 96% ee, while the methanobenzodioxepins are afforded in moderate to good yields and up to 95% ee. The reaction can proceed using catalyst loadings down to 0.25 mol%, providing one of the highest turnover numbers found in iminium ion catalysis. Furthermore, the effects involved in the substrate control of the reaction paths were investigated, relying on both experimental and computational investigations.
Publications
- Chem. Eur. J. 2016, 22, 16810
B. M. Paz, L. Klier, L. Næsborg, V. Lauridsen, F. Jensen, K. A. Jørgensen
(See online at https://doi.org/10.1002/chem.201602992) - Chem. Soc Rev. 2016
L. Klier, F. Tur, P. H. Poulsen, K. A. Jørgensen
(See online at https://doi.org/10.1039/c6cs00713a)
