Organocatalytic enantioselective construction of isatin-derived N-alkoxycarbonyl 1,3-aminonaphthols via sterically encumbered hydrocarbon-substituted quinine-based squaramide

Date

2017-09-07

Author

Karahan, SEDA
Tanyeli, Cihangir

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Herein, an illustrative example to synthesize chiral naphthoxazepine precursors via the aza-Friedel-Crafts reaction of N-alkoxycarbonyl isatin ketimines with naphthol using a new 2-adamantyl-substituted quinine-derived squaramide catalyst is presented; the reaction afforded the chiral-tetrasubstituted 3-amino-2-oxindoles with excellent enantioselectivity of greater than 99% ee and quantitative yields. To the best of our knowledge, this methodology is featured for being representative of the efficiency of sterically hindered hydrocarbon substituents in squaramide organocatalysts in terms of stereoselectivity.

Subject Keywords

Asymmetric michael addition, Conjugate addition, Contiguous stereocenters, Thiourea catalyst, Mannich reactions, Cascade, Derivatives, Nitroalkenes, Azodicarboxylates, Isocyanoacetates

URI

https://hdl.handle.net/11511/39846

Journal

NEW JOURNAL OF CHEMISTRY

DOI

https://doi.org/10.1039/c7nj01395g

Collections

Department of Chemistry, Article

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Citation Formats

S. Karahan and C. Tanyeli, “Organocatalytic enantioselective construction of isatin-derived N-alkoxycarbonyl 1,3-aminonaphthols via sterically encumbered hydrocarbon-substituted quinine-based squaramide,” NEW JOURNAL OF CHEMISTRY, pp. 9192–9202, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39846.