Novel cyclization reactions of dichloroazodienes

Tetrahedron Letters

Volumn 37, Issue 9, 1996, Pages 1351-1354

  South, Michael S ^a   Jakuboski, Terri L ^a   Westmeyer, Mark D ^a   Dukesherer, Daniel R ^a  

^a MONSANTO COMPANY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

PYRIDAZINE DERIVATIVE; PYRROLE DERIVATIVE;

ARTICLE; CYCLIZATION; DRUG SYNTHESIS; REACTION ANALYSIS; TECHNIQUE;

EID: 0029970525     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)00020-2     Document Type: Article

References (32)

1. (a) Clarke, S. J.; Gilchrist, T. L. J. Chem. Res. (S) 1985, 310; J. Chem. Res. (M) 1985, 3371.
2. (a) Clarke, S. J.; Gilchrist, T. L. J. Chem. Res. (S) 1985, 310; J. Chem. Res. (M) 1985, 3371.
3. (b) Clarke, S. J.; Davies, D. E.; Gilchrist, T. L. J. Chem. Soc., Perkin Trans. I 1983, 1803.
4. (c) Gilchrist, T. L.; Richards, P. Synthesis 1983, 153.
5. (d) Faragher, R.; Gilchrist, T. L. J. Chem. Soc., Perkin Trans. I 1979, 249.
6. (e) Sommer, S. Tetrahedron Letters 1977, 117.
7. (f) Sommer, S. Chem. Letters 1977, 583.
8. (g) Sommer, S. Angew. Chem., Int. Ed. Engl. 1977, 16, 58.
9. (h) Faragher, R.; Gilchrist, T. L. J. Chem. Soc., Chem. Commun. 1976, 581.
10. (h) Attanasi, O. A.; Caglioti, L. Org. Prep. Proceed. Int. 1986, 18, 299.
11. Several attempts have been made to aromatize a tetrahydropyridazine to a pyridazine, but none involve the use of a chloroazodiene as an intermediate, (a) Clarke, S. J.; Gilchrist, T. L. J. Chem. Res. (S) 1985, 310; J. Chem. Res. (M) 1985, 3371.
12. Several attempts have been made to aromatize a tetrahydropyridazine to a pyridazine, but none involve the use of a chloroazodiene as an intermediate, (a) Clarke, S. J.; Gilchrist, T. L. J. Chem. Res. (S) 1985, 310; J. Chem. Res. (M) 1985, 3371.
13. (b) Vors, J. J. Heterocyclic Chem. 1990, 27, 579.
14. (c) Cocco, M. T.; Congiu, C.; Maccioni, A.; Plumitallo, A. Gazz. Chim. Ital. 1988, 118, 187.
15. (a) South, M. S.; Miller, M. J., U. S. Patent Application Pending,
16. (b) South, M. S., U. S. Patent Application Pending.
17. (c) South, M. S.; Moedritzer, K. A., U. S. Patent Application Pending.
18. (d) South, M. S.; Jakuboski, T. L., U. S. Patent Application Pending.
19. South, M. S.; Jakuboski, T. L. Tetrahedron Letters 1995, 5703.
20. Two reports of a cycloaddition reaction involving a chloroazodiene have appeared, but these products were not elaborated to pyridazines. (a) Gilchrist, T. L.; Sanchez Romero, O. A.; Wasson, R. C. J. Chem. Soc., Perkin Trans. I 1989, 353.
21. (b) Gilchrist, T. L.; Stevens, J. A. J. Chem. Soc., Perkin Trans. I 1985, 1741.
22. Gilchrist, T. L.; Stevens, J. A. J. Chem. Soc. Perkin Trans. I, 1985, 1737 and references cited therein.
23. The electron rich olefins in Table 1 and 2 were available commercially or prepared via published procedures that involve refluxing 1 eq. of the appropriate aldehyde or ketone with an excess of the secondary amine in toluene or benzene over a Dean-Stark trap until the theoretical amount of water was collected. See: March , J., Advanced Organic Chemistry; 3rd Ed., John Wiley and Sons, New York, NY, p 689, 796-798. All of the electron rich olefins had the trans geometry as evidenced by the large coupling constant of the vinyl protons of 10-16 Hz.
24. 13C NMR, and elemental analyses.
25. A potential intermediate in the N-aminopyrrole formation:
26. (equation presented)
27. The regiochemistry of the double bonds is not known.
28. +).
29. +).
30. + 1).
31. +).
32. 2Cl: C, 69.67; H, 5.85; N, 10.83. Found: C, 69.41; H, 5.83; N, 10.74.