Synthesis of bifunctional 2-aminodmap/prolinamide organocatalysts and their use in asymmetric michael reaction to afford warfarin

Akkoca, Hasan Ufuk
In the first part of this thesis, the construction of the novel bifunctional proline-(1R,2R)-2-aminoDMAP organocatalyst backbone is described. Target compound has both Lewis base and Brønsted acid catalaphoric sites. The Lewis base site is synthesized via selective mono-N-pyridilization of trans-(1R,2R)-cyclohexane-1,2-diamine by Cu catalysis and Brønsted acid site is subsequently introduced by anchoring L-proline unit. In the second part, catalytic activities of organocatalysts are tested in asymmetric Michael addition reaction between a cyclic 1,3-dicarbonyl compound 4-hydroxycoumarin and various α,β-unsaturated ketones to afford optically active warfarin as anticoagulants, in one step. Reaction parameters such as solvent, temperature, equivalency, and cocatalyst were screened. Enantiomeric excess value (ee) up to 72% is attained.


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Citation Formats
H. U. Akkoca, “Synthesis of bifunctional 2-aminodmap/prolinamide organocatalysts and their use in asymmetric michael reaction to afford warfarin,” M.S. - Master of Science, Middle East Technical University, 2012.