Enantioselective Michael Addition of Nitroalkanes to Nitroalkenes Catalyzed by Chiral Bifunctional Quinine-Based Squaramides

Date

2016-01-01

Author

KANBEROĞLU, Esra
Tanyeli, Cihangir

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A family of chiral bifunctional acid-/base-type quinine/squaramide organocatalysts is shown to be highly active promoters of the conjugate addition of 1-nitropropane to various trans--nitroalkenes. The cooperation of the quinine and the sterically encumbered squaramide moieties catalyzed the Michael addition reactions at 0 degrees C by using a catalyst loading of only 2mol% to afford the 1,3-dinitro Michael adducts with excellent enantioselectivity and diastereoselectivity (up to 95%ee and syn/anti isomers up to 96:4).

Subject Keywords

Asymmetric catalysis, Enantioselectivity, Michael addition, Nitro compounds, Organocatalysis

URI

https://hdl.handle.net/11511/47559

Journal

ASIAN JOURNAL OF ORGANIC CHEMISTRY

DOI

https://doi.org/10.1002/ajoc.201500339

Collections

Department of Chemistry, Article

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Enantioselective Michael Addition of Nitroalkanes to Nitroalkenes Catalyzed by Chiral Bifunctional Quinine-Based Squaramides Kanberoğlu, Esra; Tanyeli, Cihangir (Wiley, 2015-10-26) A family of chiral bifunctional acid-/base-type quinine/squaramide organocatalysts is shown to be highly active promoters of the conjugate addition of 1-nitropropane to various trans-β-nitroalkenes. The cooperation of the quinine and the sterically encumbered squaramide moieties catalyzed the Michael addition reactions at 0 °C by using a catalyst loading of only 2 mol % to afford the 1,3-dinitro Michael adducts with excellent enantioselectivity and diastereoselectivity (up to 95 % ee and syn/anti isomers
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Citation Formats

E. KANBEROĞLU and C. Tanyeli, “Enantioselective Michael Addition of Nitroalkanes to Nitroalkenes Catalyzed by Chiral Bifunctional Quinine-Based Squaramides,” ASIAN JOURNAL OF ORGANIC CHEMISTRY, pp. 114–119, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47559.