Asymmetric Catalysis; 138: [1] Synthesis of Enantiomerically Pure 2-Pyridinyl-α-ethanols via Diastereomeric Camphanic Esters

Abstract

New terdentate facially binding ligands based on the 2-pyridinyl-α-ethanol skeleton were prepared as the racemates. Reaction with the enantiomerically pure (-)-(1S,4R)-camphanoyl chloride gave diastereomeric camphanic esters. The pure diastereomers were accessible by separating the diastereomeric esters with medium-pressure silica gel chromatography or fractional crystallization. X-ray structure analysis of the pure camphanic esters established the absolute configurations of the 2-pyridinyl-α-alcohols. The enantiomerically pure alcohols were obtained after saponification of the diastereomerically pure esters.

Key words

facial coordination - terdentate ligands - chiral 2-pyridinyl-α-alcohols - absolute configuration

References

• 1 Part 137: Brunner H. Kagan HB. Kreutzer G. Tetrahedron: Asymmetry  2001,  12:  497 
• 3 Horner L. Siegel H. Büthe H. Angew. Chem. Int. Ed. Engl.  1968,  9:  942 
• 4 Knowles WS. Sabacky MJ. J. Chem. Soc., Chem. Commun.  1968,  1445 
• 5 Brunner H. Zettlmeier W. Handbook of Enantioselective Catalysis   Vol. I and II:  VCH; Weinheim: 1993. 
• 6 Brunner H. Angew. Chem. Int. Ed.  1999,  38:  1194 
• 7 Mauleón D. Pujol MD. Minguillón C. Miquel J. J. Heterocycl. Chem.  1989,  26:  693 
• 8 Orrenius C. Mattson A. Norin T. Öhrner N. Hult K. Tetrahedron: Asymmetry  1994,  5:  3041 
• 9 Thurkauf A. Mattson MV. Richardson S. Mirsadeghi S. Ornstein PL. Harrison EA. Rice KC. Jacobson AE. Monn JA. J. Med. Chem.  1992,  35:  1323 
• 11 MijoloviĘ D. Ph. D. Thesis   Universität Regensburg; Germany: 2001. 
• 12 Sharpless BK. Amberg W. Bennani YL. Crispino GA. Hartung J. Jeong K. Kwong H. Morikawa K. Wang Z. Xu D. Zhang X. J. Org. Chem.  1992,  57:  2768 
• 13 Genzel Y. Archelas A. Broxterman QB. Schulze B. Furstoss R. Tetrahedron: Asymmetry  2000,  11:  3041 
• 14 Palucki M. McCormick GJ. Jacobsen EN. Tetrahedron Lett.  1995,  36:  5457 
• 15 Brunner H. Kürzinger A. J. Organomet. Chem.  1988,  346:  413 
• 16 Kitamura M. Ohkuma T. Inoue S. Sayo N. Kumobayashi H. Akutagawa S. Ohta T. Takaya H. Noyori R. J. Am. Chem. Soc.  1988,  110:  629 
• 17 Kitamura M. Tokunaga M. Ohkuma T. Noyori R. Org. Synth.  1998,  Coll. Vol. IX:  589 
• 18 Ishizaki M. Fujita K. Shimamoto M. Hoshino O. Tetrahedron: Asymmetry  1994,  5:  411 
• 19 Gerlach H. Kappes D. Boeckman RK. Maw GN. Org. Synth.  1998,  Coll. Vol. IX:  151 
• 20 Bolm C. Ewald M. Felder M. Schlinghoff G. Chem. Ber.  1992,  125:  1169 

2

X-ray structure analyses.

10

Crystallographic data (excluding structure factors)for the structures in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication nos. CCDC 162515 [for (±)-3], CCDC 162518 [for (±)-5], CCDC 162514 [for(diphenylphosphanyl)methyl-2-pyridinylketone], CCDC 162512 [for(phenylsulfanyl)methyl-2-pyridinylketone], CCDC 162513 [for (2S,4S)-2-(2-pyridinyl)-4-carboethoxy-1,3-thiazolidine: BESTHIA], CCDC 162516 [for (S)-(-)-9], CCDC 162520 [for (R)-(-)-11], CCDC 162517 [for (S)-(+)-12] and CCDC 162519 [for (R)-(-)-13]. Copies of the data can be obtained, free of charge, on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: [phone] or e-mail: [e-mail]).