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

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2015
Susam, Dilşad
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 quinine based novel bifunctional organocatalyst, which has been developed in our group, up to 91% ee under the optimized condition with 10 mol% catalyst loading. In the second part of the thesis, preliminary studies of enantioselective Henry, aldol, decarboxylative aldol and Friedel-Crafts type substitution domino reactions were conducted with bifunctional organocatalysts. Among these studies, the best result was achieved with Friedel-Crafts type substitution domino reaction as 92% ee in 10 minutes.

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Citation Formats
D. Susam, “Enantioselective aza-Henry reaction of t-boc protected imines and nitroalkanes with bifunctional squaramide organocatalysts,” M.S. - Master of Science, Middle East Technical University, 2015.