Proline mediated asymmetric ketol cyclization: A template reaction

Tetrahedron Asymmetry

Volumn 10, Issue 9, 1999, Pages 1631-1634

  Rajagopal, D ^a   Moni, M S ^b   Subramanian, S ^b   Swaminathan, S ^a  

^a UNIVERSITY OF MADRAS   (India)

^b INDIAN INSTITUTE OF TECHNOLOGY MADRAS   (India)

Author keywords

[No Author keywords available]

Indexed keywords

KETOL; PROLINE;

ARTICLE; CARBON NUCLEAR MAGNETIC RESONANCE; CYCLIZATION; INFRARED SPECTROSCOPY; PRIORITY JOURNAL; PROTON NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS;

EID: 0033532310     PISSN: 09574166     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0957-4166(99)00174-3     Document Type: Article

References (19)

1. Rajagopal, D.; Rajagopalan, K.; Swaminathan, S. Tetrahedron: Asymmetry 1996, 7, 2189.
2. (a) Hajos, Z. G.; Parrish, D. R. J. Org. Chem. 1974, 39, 1615.
3. (b) Hajos, Z. G.; Parrish, D. R. Org. Synth. 1985, 63, 26.
4. (c) Hajos, Z. G.; Parrish, D. R. US Patent 3975440, 1976.
5. Eder, U.; Sauer, G.; Weichert, R. Angew. Chem., Int. Ed. Engl. 1971, 10, 496.
6. Buchschacher, P.; Furst, A. Org. Synth. 1985, 63, 37.
7. Agami, C.; Meynier, F.; Puchot, C.; Guilhem, J.; Pascard, C. Tetrahedron 1984, 40, 1031.
8. Sarkar, A.; Jois, H. R. Y.; Kasthuri, T. R.; Dasgupta, D.; Proc. Indian Acad. Sci., Chem. Sci. 1982, 91, 475.
9. (a) NMR spectra were recorded on a JEOL 400 MHz GSX model.
10. (b) IR spectra were recorded on a NICOLET AVATAR 360 FTIR EST with Multi Bounce HATR.
11. Dr. Hajos has drawn our attention to US Patent 3975440, 1976 where the synthesis of S-3 without using solvents was reported earlier.
12. 2a that there was no reaction between trione 1 and 2S-trans-4-hydroxy proline and ruled out any solid state reaction.
13. Similar deprotonation by crystalline salts of carboxylic acids occur in the Perkin reaction.
14. 13C NMR studies of reaction between ketones like cyclohexanone, cyclopentanone and ethyl methyl ketone in DMSO with S-proline did not show any evidence of reaction.
15. (a) Ferran Jr., H. E.; Drake, D. A.; Spencer, T. A. J. Org. Chem. 1975, 40, 2017.
16. (b) Hupe, D. J.; Kendall, M. C. R.; Spencer, T. A. J. Am. Chem. Soc. 1973, 95, 2271.
17. We can invoke this template mechanism also for the antibody catalyzed enantioselective conversion of trione 2 to S-4 reported recently by Zhong, G.; Hofmann, T.; Lenner, R. A.; Danishefsky, S.; Barbas, C. J. Am. Chem. Soc. 1997, 119, 8131.
18. We are thankful to the referee for drawing our attention to the following two references where a similar surface reaction has been invoked: (a) Shvo, Y.; Gal, M.; Becker, Y.; Elgavi, A. Tetrahedron: Asymmetry 1996, 7, 911.
19. (b) Thoen, J. C.; Lipton, M. A. Tetrahedron: Asymmetry 1997, 8, 3947.