Stereoselective synthesis of optically active cyclopenta[c]pyridines and tetrahydropyridines

2012-05-15
SEZER, Serdar
GÜMRÜKÇÜ, Yasemin
BAKIRCI, Irem
Unver, M. Yagiz
Tanyeli, Cihangir
The intramolecular Pauson-Khand and ring closing metathesis (RCM) reactions of nitrogen containing chiral enynes and dienes are described. The enyne and diene systems comprised of N-propargylated and N-allylated units are constructed on chiral homoallylic or homopropargylic alcohol backbones, respectively, via S(N)2 and/or modified Mitsunobu reactions. The racemic homoallylic and homopropargylic alcohol derivatives were successfully resolved in high ee (93-99%) by applying chemoenzymatic methods using various lipases such as PS-C II, Lipozyme, and CAL-B. Each enantiomerically enriched enyne afforded the most conformationally stable diastereomeric cyclopenta[c]pyridine ring system as the sole product, whereas enantiomerically enriched dienes gave tetrahydropyridine derivatives as a result of intramolecular Pauson-Khand and RCM reactions, respectively.
TETRAHEDRON-ASYMMETRY

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Citation Formats
S. SEZER, Y. GÜMRÜKÇÜ, I. BAKIRCI, M. Y. Unver, and C. Tanyeli, “Stereoselective synthesis of optically active cyclopenta[c]pyridines and tetrahydropyridines,” TETRAHEDRON-ASYMMETRY, pp. 662–669, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39302.