Solution structure of a chiral dialkylboron enolate by NMR spectroscopy and simulated annealing: Unusual stabilization of this intermediate by a baron-nitrogen interaction

Journal of Organic Chemistry

Volumn 65, Issue 16, 2000, Pages 5031-5033

  Baringhaus, Karl Heinz ^a   Matter, Hans ^a   Kurz, Michael ^a  

^a SANOFI AVENTIS DEUTSCHLAND GMBH   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

BORON DERIVATIVE;

ARTICLE; CHEMICAL STRUCTURE; CHIRALITY; CONFORMATION; NUCLEAR MAGNETIC RESONANCE;

EID: 0034637621     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo0001885     Document Type: Article

References (34)

1. (a) Evans, D. A.; Nelson, J. V.; Taber, T. Top. Stereochem. 1982, 13, 1-115.
2. (b) Evans, D. A. Aldrichim. Acta 1982, 15, 23-32.
3. (c) Heathcock, C. H. In Asymmetric Synthesis; Morrison, J. D., Ed.; Academic Press: New York, 1983; Vol. 3, pp 111-212.
4. (a) Masamune, S.; Mori, S.; Van Horn, D.; Brooks, D. W. Tetrahedron Lett. 1979, 1665-1668.
5. (b) Hirama, M.; Garvey, D. S.; Lu, L.; Masamune, S. Tetrahedron Lett. 1979, 3937-3940.
6. (c) Evans, D. A.; Nelson, J. V.; Vogel, E.; Taber, T. R. J. Am. Chem. Soc. 1981, 103, 3099-3111.
7. (d) Evans, D. A.; Bartroli, J.; Shih, T. L. J. Am. Chem. Soc. 1981, 103, 2127-2129.
8. (e) Masamune, S.; Choy, W.; Kerdesky, F. A. J.; Imperiali, B. J. Am. Chem. Soc. 1981, 703, 1566-1568.
9. (f) Gennari, C.; Cardani, S.; Colombo, L.; Scolastico, C. Tetrahedron Lett. 1984, 25, 2283-2286.
10. (g) Prashad, M.; Mahavir, K.; Kim, H.-Y.; Lu, Y.; Liu, Y.; Har, D.; Repic, O.; Blacklock, T. J.; Giannousis, P. J. Org. Chem. 1999, 64, 1750-1753.
11. Evans, D. A.; Rieger, D. L.; Bilodeau, M. T.; Urpi, F. J. Am. Chem. Soc. 1991, 113, 1047-1049.
12. (a) Ager, D. J.; Prakash, I.; Schaad, D. R. Chem. Rev. 1996, 96, 835-875.
13. (b) Ager, D. J.; Prakash, I.; Schaad, D. R. Aldrichim. Acta 1997, 30, 3-12.
14. 2 were collected using a sweep width of 8 ppm in the proton and 165 ppm in the carbon dimension. The HMBC (Bax, A.; Summers, M. F. J. Am. Chem. Soc. 1986, 108, 2093-2094.
15. 2 were collected using a sweep width of 8 ppm in the proton and 165 ppm in the carbon dimension. The HMBC (Bax, A.; Summers, M. F. J. Am. Chem. Soc. 1986, 108, 2093-2094.
16. 2 were collected using a sweep width of 8 ppm in the proton and 165 ppm in the carbon dimension. The HMBC (Bax, A.; Summers, M. F. J. Am. Chem. Soc. 1986, 108, 2093-2094.
17. 2 were collected using a sweep width of 8 ppm in the proton and 165 ppm in the carbon dimension. The HMBC (Bax, A.; Summers, M. F. J. Am. Chem. Soc. 1986, 108, 2093-2094.
18. 2 were collected using a sweep width of 8 ppm in the proton and 165 ppm in the carbon dimension. The HMBC (Bax, A.; Summers, M. F. J. Am. Chem. Soc. 1986, 108, 2093-2094.
19. (a) Pachler, K. G. R. Spectrochim. Acta 1963, 19, 2085-2092.
20. (b) Pachler, K. G. R. Spectrochim. Acta 1964, 20, 581-587.
21. Kessler, H. Angew. Chem., Int. Ed. Engl. 1982, 21, 512-523.
22. (a) Nilges, M. ; Clore, G. M.; Gronenborn, A. M. FEBS Lett. 1988, 229, 317-324.
23. (b) Brünger, A. T.; Adams, P. A.; Rice, L. M. Structure 1997, 5, 325-336.
24. All modelling work was performed using SYBYL (Versions 6.4 and 6.5, Tripos, St. Louis, MO, 1998.) on Silicon Graphics workstations. A time step of 0.5 fs was used for the integration of Newton's equation of motion. Kinetic energy was included by coupling the system to a thermal bath (Berendsen, H. J. C.; Postma, J. P. M.; van Gunsteren, W. F.; Di Nola, A.; Haak, J. R. J. Chem. Phys. 1984, 81, 3684-3690).
25. Stewart, J. J. P.; Seiler, F. J. MOPAC (Version 6.0), QCPE program No. 455, Quantum Chemistry Program Exchange, University of Indiana, Bloomington, IN, 1989.
26. (a) Dewar, M. J. S.; Zoebisch, E. G.; Healy, E. F.; Stewart, J. J. P. J. Am. Chem. Soc. 1985, 107, 3902-3907.
27. (b) Dewar, M. J. S.; Jie, C.; Zoebisch, E. G. Organometallics 1988, 7, 513-521.
28. Clark, M.; Cramer, R. D.; Van Opdenbosch, N. J. Comput. Chem. 1989, 10, 982-1912.
29. Widmer, H.; Widmer, A.; Braun, W. J. Biomol. NMR 1993, 3, 307-324.
30. Full geometry optimization level using all bonds and angles, the convergence option precise and the additional MOPAC keywords NOMM, and XYZ were used.
31. (a) Köster, R.; Kucznierz, R.; Schüssler, W.; Bläser, D.; Böse, R. Liebigs Ann. Chem. 1993, 189-200.
32. (b) Ansorge, A.; Brauer, D. J.; Bürger, H.; Dörrenbach, F.; Hagen; Pawelke, G.; Weuter, W. J. Organomet. Chem. 1990, 396, 253-267.
33. (c) CSD Refcode SUHNUE, VIBZEL.
34. Cambridge Structural Database (CSD), UNITY release 5.15, Cambridge Crystallographic Data Center (CCDC), Cambridge, UK, 1998.