Asymmetric synthesis of norbornene based 1,4-Aminoalcohol derivatives and applications in asymmetric diethylzinc reactions

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2007

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Erdem, Mine

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The asymmetric synthesis of chiral norbornene based 1,4-aminoalcohols and their applications in asymmetric diethylzinc addition reactions was perfomed starting from meso-anhydride 50. The desymmetrization of this meso-anhydride 50 was done by the usage of quinine or quinidine cinchona alkaloids with very high enantiomeric excess values (up to 98% ee) and chemical yields. The Quinidine-mediated desymmetrization of meso-anhydride 50 with methanol gave (2R,3S)-(+)-cis-monoester 51. The amination of this resulting compound with HMPTA was performed and by keeping the amine group constant, the amidoester was transformed into chiral ligands with Grignard reaction followed by LAH reduction. The effectiveness of 1,4-aminoalcohol type ligands, (2R,3S)-(-)-57, (2R,3S)-(-)-58, (2R,3S)-(-)-59 and (2S,3R)-(+)-60 as chiral catalysts in asymmetric diethylzinc addition reaction to benzaldehyde were examined and the ligand 60 gave the highest enantioselectivity (69% e.e.)

Subject Keywords

Chemistry, Organic

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http://etd.lib.metu.edu.tr/upload/12608318/index.pdf
https://hdl.handle.net/11511/16666

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Erdem, “Asymmetric synthesis of norbornene based 1,4-Aminoalcohol derivatives and applications in asymmetric diethylzinc reactions,” M.S. - Master of Science, Middle East Technical University, 2007.