A new dynamic resolution strategy for asymmetric synthesis

Tetrahedron Letters

Volumn 37, Issue 8, 1996, Pages 1301-1304

  Caddick, Stephen ^a   Jenkins, Kerry ^a  

^a UNIVERSITY OF SUSSEX   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

2 PYRROLIDONE DERIVATIVE;

ARTICLE; CHIRALITY; DRUG STRUCTURE; DRUG SYNTHESIS; MOLECULAR DYNAMICS; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030023044     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(95)02379-8     Document Type: Article

References (21)

1. For recent review articles: Noyori, R.; Tokunaga, M.; Kitamura, M. Bull. Chem. Soc. Jpn., 1995, 68, 36-56; Ward, R. S. Tetrahedron:Asymmetry, 1995, 6, 1475-1490.
2. For recent review articles: Noyori, R.; Tokunaga, M.; Kitamura, M. Bull. Chem. Soc. Jpn., 1995, 68, 36-56; Ward, R. S. Tetrahedron:Asymmetry, 1995, 6, 1475-1490.
3. (a) Ward, R. S.; Pelter, A.; Goubet, D.; Pritchard, M. C. Tetrahedron:Asymmetry, 1995, 6, 469-498;
4. (b) Kubo, A.; Takahashi, M.; Kubota, H.; Nunami, K. Tetrahedron Lett. 1995, 36, 6251-6252;
5. (c) Kubota, H.; Kubo, A.; Takahashi, M.; Shimizu, R.; Tadamasa, D.; Okamura, K.; Nunami, K. J.Org.Chem. 1995, 60, 6776-6784;
6. (d) Koh, K.; Durst, T. J.Org.Chem., 1994, 59, 4683-4686;
7. (e) O'Meara, J. A.; Jung, M.; Durst, T. Tetrahedron Lett. 1995, 36, 2559-2562; ibid.5096;
8. (e) O'Meara, J. A.; Jung, M.; Durst, T. Tetrahedron Lett. 1995, 36, 2559-2562; ibid.5096;
9. (f) Koh, K.; Ben, R. N.; Durst, T. Tetrahedron Lett. 1993, 34, 4473-4476;
10. (g) Turner, N. J.; Winterman, J. R.; McCague, R.; Parratt, J. S.; Taylor, S. J. C. Tetrahedron Lett. 1995, 36, 1113-1116
11. Close, W. J. J.Org.Chem. 1950, 15, 1131; Roder, H.; Helmchen, G.; Peters, E.-M.; Peters, K.; von Schnering, H.-G. Angew. Chem. Int. Ed. Engl. 1984, 23, 898-899.
12. Close, W. J. J.Org.Chem. 1950, 15, 1131; Roder, H.; Helmchen, G.; Peters, E.-M.; Peters, K.; von Schnering, H.-G. Angew. Chem. Int. Ed. Engl. 1984, 23, 898-899.
13. 8-THF at room temperature.
14. The absolute stereochemistry of the 2'S-2 diastereomer was confirmed by X-ray crystallography.
15. Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience, 1993; pp. 297-464; Jacques, J.; Collet, A.; Wilen, S. H. Enantiomers, Racemates, and Resolutions; Wiley-Interscience, 1981; pp. 369-378; Harris. M. M. Progr. Stereochem. 1958, 2, 157-195 and references therein.
16. Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience, 1993; pp. 297-464; Jacques, J.; Collet, A.; Wilen, S. H. Enantiomers, Racemates, and Resolutions; Wiley-Interscience, 1981; pp. 369-378; Harris. M. M. Progr. Stereochem. 1958, 2, 157-195 and references therein.
17. Eliel, E. L.; Wilen, S. H.; Mander, L. N. Stereochemistry of Organic Compounds; Wiley-Interscience, 1993; pp. 297-464; Jacques, J.; Collet, A.; Wilen, S. H. Enantiomers, Racemates, and Resolutions; Wiley-Interscience, 1981; pp. 369-378; Harris. M. M. Progr. Stereochem. 1958, 2, 157-195 and references therein.
18. TLC analysis of a range of solvents containing the individual diastereomers of 2 indicated that no significant epimerisation occurred after one week in any of the following solvents: petrol, diethyl ether, ethyl acetate, dichloromethane, methanol, acetonitrile.
19. D -41.0. (See also Ref. 2(c) for the R enantiomer.)
20. The slower rate of epimerisation of 2'R-2 and the fact that this diastereomer predominates at equilibrium indicates that it is thermodynamically more stable. We have also made the qualitative observation that 2'S-2 generally reacts faster than 2'R-2 in alkylation reactions using the individual diastereomers of 2.
21. 4NBr appears to be comparable we suspect that the enhanced selectivity is achieved by the relative reactivities of iodo derivatives of 2'R-2 and 2'S-2 generated in-situ; though this is still to be confirmed.