Enantioselective aza-Henry reaction of t-Boc protected imines and nitroalkanes with bifunctional squaramide organocatalysts

Date

2017-05-07

Author

Susam, Zeynep Dilşad
Tanyeli, Cihangir

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An organocatalytic asymmetric aza-Henry reaction of t-Boc protected imines with nitroalkanes has been established by chiral acid-base type bifunctional Cinchona alkaloid/squaramide organocatalysts. The cooperation of a quinine motif as a base and sterically encumbered squaramide (H-bond donor) enabled mostly complete conversion of a range of reactants into the corresponding aza-Henry products at room temperature with good selectivities (up to 91% ee with 10 mol% catalyst loading).

Subject Keywords

Nitro-mannich reactions, Michael addition, Bearing

URI

https://hdl.handle.net/11511/33133

Journal

NEW JOURNAL OF CHEMISTRY

DOI

https://doi.org/10.1039/c6nj04078k

Collections

Department of Chemistry, Article

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Enantioselective aza-Henry reaction of t-boc protected imines and nitroalkanes with bifunctional squaramide organocatalysts Susam, Dilşad; Tanyeli, Cihangir; Department of Chemistry (2015) The first part of this thesis comprises the application of a Cinchona alkaloid derived, bifunctional squaramide organocatalyst in the aza-Henry reaction of t-Boc protected imines and nitroalkanes. The target chiral β-nitroamines are chosen because; they are quite feasible for the corresponding α-amino acids and 1,2-diamines, which are basic structural motif in many natural products and key materials of the many pharmaceuticals. In this part, 12 different chiral β-nitroamine derivatives were synthesized with...

Citation Formats

Z. D. Susam and C. Tanyeli, “Enantioselective aza-Henry reaction of t-Boc protected imines and nitroalkanes with bifunctional squaramide organocatalysts,” NEW JOURNAL OF CHEMISTRY, pp. 3555–3561, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/33133.