Bifunctional squaramide catalyzed stereoselective Mannich reaction of alpha-azido ketones with isatin-derived ketimines

2020-01-21
KARAHAN, SEDA
Tanyeli, Cihangir
Asymmetric organocatalytic Mannich reaction of alpha-azido ketones and N-Boc protected isatin-derived ketimines were investigated for the first time. Examination of both 2-adamantyl and 3,5-bis(trifluoromethyl)aniline substituted quinine-based squaramides afforded chiral Mannich bases with two contiguous stereogenic centers in high yields (up to 97%) and stereoselectivity (up to dr = 24 : 1 syn : anti and 96% ee). Azido and masked amino functionalities of the potent heterocycle precursor adducts were utilized in representative examples.
ORGANIC & BIOMOLECULAR CHEMISTRY

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Citation Formats
S. KARAHAN and C. Tanyeli, “Bifunctional squaramide catalyzed stereoselective Mannich reaction of alpha-azido ketones with isatin-derived ketimines,” ORGANIC & BIOMOLECULAR CHEMISTRY, pp. 479–487, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41469.