Molecular Orbital Studies of the Intramolecular Reaction of Protonated cis- and trans-3,4-Epoxypentan-1-ol

Journal of Organic Chemistry

Volumn 63, Issue 12, 1998, Pages 3875-3883

  Coxon, James M ^a   Morokuma, Keiji ^b   Thorpe, Aaron J ^a   Whalen, Dale ^c  

^a UNIVERSITY OF CANTERBURY   (New Zealand)

^b UNIVERSITY OF MARYLAND BALTIMORE COUNTY   (United States)

^c EMORY UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0345874371     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo972071v     Document Type: Article

References (25)

1. Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734. See also: Norman, Sir R.; Coxon, J. M. Principles of Organic Synthesis Blackie Chapman and Hall: London, and John Wiley and Sons: New York, 1993; p 678.
2. Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734. See also: Norman, Sir R.; Coxon, J. M. Principles of Organic Synthesis Blackie Chapman and Hall: London, and John Wiley and Sons: New York, 1993; p 678.
3. Coxon, J. M.; Hartshorn, M. P.; Swallow, W. H. Aust. J. Chem. 1973, 26, 2521
4. Janda, K. D.; Shevlin, C. G.; Lerner, R. A. Science 1993, 259, 490.
5. Na, Houk, J.; Shevlin, K. N.; C. G.; Janda, Lerner, K. D.; R. A. J. Am. Chem. Soc. 1993, 115, 8453.
6. Na, J.; Houk, K. N. J. Am. Chem. Soc. 1996, 118, 9204.
7. Methods defined herein: Coxon, J. M.; Houk, K. N.; Luibrand, R. T. J. Org. Chem. 1995, 60, 418-427.
8. AM1: Dewar, M. J. S.; Zoebisch, E. G.; Healy, E. F.; Stewart, J. J. P. J. Am. Chem. Soc. 1985, 107, 3902.
9. (a) Becke, A. D. Phys. Rev. A 1988, 38, 3098.
10. (b) Becke, A. D. J. Chem. Phys. 1993, 98, 1372.
11. (c) Lee, C.; Yang, W.; Parr, R. G. Phys. Rev. B 1988, 37, 785.
12. Cf. Schreiner, P. R.; Schleyer, P. v. R.; Schaefer, H. F. J. Org. Chem. 1997, 62, 4216.
13. Gaussian 94, Revision B.1. 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.
14. Ford, G. P.; Smith, C. T. J. Am. Chem. Soc. 1987, 109, 1325.
15. Coxon, J. M.; Maclagan, R. G. A. R.; Rauk, A.; Thorpe, A. J.; Whalen, D. J. Am. Chem. Soc. 1997, 119, 4712-4718.
16. See the Supporting Information for the method of generation of the structure.
17. 12 Therefore, these two protonated diastereomers are likely to be in equilibrium via reversible protonation/deprotonation, and 17 is the most abundant protonated form of the cis-epoxide.
18. The lowest energy conformer 14 with the ether proton syn to the hydroxyl was 5.4 kcal/mol lower in energy than the lowest energy structure protonated anti to the hydroxyl and has a hydrogen bond between O4 and H8 (2.232 Å at MP2/6-31G*). The O1-H8 bond (0.992 Å) is somewhat longer than it would be in the absence of this H-bonding.
19. TS 13-14 was calculated to be lower in energy by 1.0 kcal/mol (HF/6-31G* + ZPC) than when the proton was positioned syn to the epoxide substituent groups; therefore, the IRC was conducted from the anti-protonated structure (TS 13-14) even though 17 (Figure 6) is lower than 13.
20. Another transition structure involving retention of configuration for the conversion of 13 to 18 was found at the HF/3-21G* level with a high barrier of 14.3 kcal/mol (HF/3-21G* + ZPC). However, this structure does not exist at higher levels of theory.
21. Fukui, K.; Kato, S.; Fujimoto, H. J. Am. Chem. Soc. 1975, 97, 1. Ishida, K.; Morokuma, K.; Komornicki, A. J. Chem. Phys. 1977, 66, 2153.
22. Fukui, K.; Kato, S.; Fujimoto, H. J. Am. Chem. Soc. 1975, 97, 1. Ishida, K.; Morokuma, K.; Komornicki, A. J. Chem. Phys. 1977, 66, 2153.
23. A movie file has been deposited with the Supporting Information.
24. A detailed analysis of the changes in bond lengths and angles in this process is included in the Supporting Information.
25. A detailed analysis of the IRC is given in the Supporting Information.