Theozymes for intramolecular ring cyclization reactions

Journal of the American Chemical Society

Volumn 121, Issue 47, 1999, Pages 10955-10957

  Coxon, James M ^a   Thorpe, Aaron J ^a  

^a UNIVERSITY OF CANTERBURY   (New Zealand)

Author keywords

[No Author keywords available]

Indexed keywords

EPOXIDE; FURAN; HAPTEN; IMMUNOGLOBULIN F(AB) FRAGMENT; IMMUNOGLOBULIN G ANTIBODY; PYRAN;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; CONFORMATIONAL TRANSITION; CRYSTAL STRUCTURE; CYCLIZATION; MODEL;

EID: 0033486085     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja991430w     Document Type: Article

References (21)

1. Janda, K. D.; Shelvin, C. G.; Lerner, R. A. Science 1993, 259, 490-493. Janda, K. D.; Shelvin, C. G.; Lerner, R. A. J. Am. Chem. Soc. 1995, 117, 2659-2660.
2. Janda, K. D.; Shelvin, C. G.; Lerner, R. A. Science 1993, 259, 490- 493. Janda, K. D.; Shelvin, C. G.; Lerner, R. A. J. Am. Chem. Soc. 1995, 117, 2659-2660.
3. No tetrahydrofuran could be detected in the product.
4. Coxon, J. M.; Hartshorn, M. P.; Swallow, W. H. Aust. J. Chem. 1973, 26, 2521-2526.
5. This preference was subsequently encapsulated in the rules for ring closure enunciated by: Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734. See also: Norman, R.; Coxon, J. M. Principles of Organic Synthesis; Blackie Chapman and Hall: London and John Wiley and Sons: New York. 1993: p 678. Baldwin, J. E.; Lusch, M. J. Tetrahedron 1982, 19, 2939.
6. This preference was subsequently encapsulated in the rules for ring closure enunciated by: Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734. See also: Norman, R.; Coxon, J. M. Principles of Organic Synthesis; Blackie Chapman and Hall: London and John Wiley and Sons: New York. 1993: p 678. Baldwin, J. E.; Lusch, M. J. Tetrahedron 1982, 19, 2939.
7. This preference was subsequently encapsulated in the rules for ring closure enunciated by: Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734. See also: Norman, R.; Coxon, J. M. Principles of Organic Synthesis; Blackie Chapman and Hall: London and John Wiley and Sons: New York. 1993: p 678. Baldwin, J. E.; Lusch, M. J. Tetrahedron 1982, 19, 2939.
8. Na, J.; Houk, K. N.; Shelvin, C. G.; Janda, K. D.; Lerner, R. A. J. Am. Chem. Sao. 1993, 115, 8453-8454. "Formation of the 5-exo-product is predicted to be favored by about 1.8 kcal/mol in aqueous solution. This should produce a 96:4 5-exo:6-endo ratio. To favor the 6-endo product by a similar amount, the catalytic antibody must lower the 6-endo activation energy 3.6 kcal/mol more than it lowers the 5-exo activation energy."
9. Chem. Eng. News 1996, Sept 30th, 35. "Using the theozyme technique, Houk has explained and experimentally verified why the reactions of a hydroxy epoxide catalysed by an antibody yields a tetrahydropyran rather than the tetrahydrofuran largely produced with acid or base catalysis."
10. We had previously calculated transition structures for furan and pyran formation where the proton was syn to the methyl in epoxide 6 and 9 and 10. There is negligible difference in energy and framework geometry. Coxon, J. M.; Thorpe, A. J. J. Org. Chem. 1999, 64, 5530-5541.
11. We thank Professor Ken Houk and Dr. Jim Na tor supplying their coordinates.
12. Coxon, J. M.; Maclagan, R. G. A. R.; Rauk, A.; Thorpe, A. J.; Whalen, D. J. Am. Chem. Soc. 1997, 119, 4712-4718. Coxon, J. M.; Morokuma, K.; Thorpe, A. J.; Whalen, D. J. Org. Chem. 1998, 63, 3875- 3883.
13. Coxon, J. M.; Maclagan, R. G. A. R.; Rauk, A.; Thorpe, A. J.; Whalen, D. J. Am. Chem. Soc. 1997, 119, 4712-4718. Coxon, J. M.; Morokuma, K.; Thorpe, A. J.; Whalen, D. J. Org. Chem. 1998, 63, 3875-3883.
14. The preferential formation of furan 7 via 9 reflects a more favorable co-linear trajectory of the approaching alkyl hydroxyl and the lesser strain necessary to form the five-membered ring. See also reference 7.
15. Na, J.; Houk, K. N. J. Am. Soc. 1996, 118, 9204-9205.
16. It was envisaged that hydrogen bonding between the methanol proton and the epoxide oxygen and between the hydroxyl proton of the deprotonated transition structures 9 and 10 and the formate anion is the important feature of the catalytic stabilization. In addition the carbocation would be stabilized by the formate anion.
17. Gruber, K.; Zhou, B.; Houk, K. N.; Lerner, R. A.; Shevlin, C. G.; Wilson, I. A. Biochemistry 1999, 38, 7062-7074.
18. Gaussian 94, Revision D.2. Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Gill, P. M. W.; Johnson, B. G.; Robb, M. A.; Cheeseman, J. R.; Keith, T.; Petersson, G. A.; Montgomery, J. A.; Raghavachari, K.; Al-Laham, M. A.; Zakrzewski, V. G.; Ortiz, J. V.; Foresman, J. B.; Cioslowski, J.; Stefanov, B. B.; Nanayakkara, A.; Challacombe, M.; Peng, C. Y.; Ayala, P. Y.; Chen, W.; Wong, M. W.; Andres, J. L.; Replogle, E. S.; Gomperts, R.; Martin, R. L.; Fox, D. J.; Binkley, J. S.; Defrees, D. J.; Baker, J.; Stewart, J. P.; Head-Gordon, M.; Gonzalez, C.; Pople, J. A. Gaussian, Inc.: Pittsburgh, PA, 1995.
19. 11
20. We recognise the important contribution by Houk in support of electrostatic catalytic stabilization from a theozyme, and believe an alternate positioning of the methanol/formate ion is required to support the experimental result.
21. The reported model is not a global minima complex.