New pinene-derived pyridines as bidentate chiral ligands

Malkov, A. V., Stewart-Liddon, A. J. P., Teply, F., Kobr, L., Muir, K. W., Haigh, D. and Kocovsky, P. (2008) New pinene-derived pyridines as bidentate chiral ligands. Tetrahedron, 64(18), pp. 4011-4025. (doi: 10.1016/j.tet.2008.02.045)

Abstract

A synthesis of new bidentate pyridines 8a-d, 9, and 10 has been developed, starting from triflate 14, readily available from beta-pinene 11. A copper complex of the pyridine-oxazoline ligands 8a has been found to catalyze asymmetric allylic oxidation of cyclic olefins 36a-c with good conversion rates and acceptable enantioselectivity (<= 67% ee). The imidazolium salt 10 has been identified as a precursor of the corresponding N,N'-unsymmetrical N-heterocyclic carbene ligand, whose complex with palladium catalyzed the intramolecular amide enolate alpha-arylation leading to oxindole 45 in excellent yield but with low enantioselectivity..

• Item Type: Articles
• Keywords: ALLYLIC OXIDATION amide Asymmetric catalysis ASYMMETRIC KETONE HYDROSILYLATION CARBENE CATALYZED CONJUGATE ADDITION Chiral chiral ligands COMPLEX COMPLEXES CONVERSION Copper COPPER-COMPLEXES ENANTIOSELECTIVE ALLYLIC OXIDATION HETEROCYCLIC CARBENE LIGANDS IMIDAZOLIUM IMIDAZOLIUM SALTS LIGAND LIGANDS N,N'-heterocyclic carbene ligands NI(II)/CR(II)-MEDIATED COUPLING REACTION NOZAKI-HIYAMA ALLYLATION OLEFINS oxazoline ligands OXIDATION Palladium Pyridine pyridine ligands pyridines RATES RECEPTOR ANTAGONISTS SALT TERT-BUTYL PERBENZOATE transition metal catalysis
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Malkov, Dr Andrei and Muir, Dr Kenneth and Teply, Dr Filip and Kocovsky, Professor Pavel
• Authors: Malkov, A. V., Stewart-Liddon, A. J. P., Teply, F., Kobr, L., Muir, K. W., Haigh, D., and Kocovsky, P.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Tetrahedron
• ISSN: 0040-4020