Asymmetric synthesis of norbornene based 1,4-amino alcohol derivatives and applications in asymmetric transformations

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2005

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Sünbül, Murat

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The asymmetric synthesis of cis-1,4-aminoalcohols with norbornene backbone was performed starting with simple and cheap anhydride 30. Quinine-mediated desymmetrization of anhydride 30 with methanol resulted in (2S,3R)-(-)-cis-hemiester 31 (98% e.e.). Chemoselective amination with HMPTA and NH4OH followed by LAH reduction afforded (2S,3R)-(+)-36 and (2S,3R)-(-)-37, respectively. The amidoester (2S,3R)-(-)-32 was transformed into chiral ligand (2S,3R)-(-)-35 with Grignard reaction followed by LAH reduction. The chiral ligands (2S,3R)-(-)-35, (2S,3R)-(+)-36 and (2S,3R)-(-)-37 were subjected to asymmetric diethylzinc addition reaction to examine their effectiveness as chiral catalyst. Among these, chiral ligand 36 exhibited the highest enantioselectivity (88% e.e.)

Subject Keywords

Chemistry, Organic

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http://etd.lib.metu.edu.tr/upload/12606174/index.pdf
https://hdl.handle.net/11511/15156

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Sünbül, “Asymmetric synthesis of norbornene based 1,4-amino alcohol derivatives and applications in asymmetric transformations,” M.S. - Master of Science, Middle East Technical University, 2005.