Regioselective synthesis of indoles via reductive annulation of nitrosoaromatics with alkynes

Organic Letters

Volumn 4, Issue 5, 2002, Pages 699-701

  Penoni, Andrea ^a   Volkmann, Jerome ^a   Nicholas, Kenneth M ^a  

^a UNIVERSITY OF OKLAHOMA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001692848     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol017139e     Document Type: Article

References (37)

1. Sundberg, R. J. Indoles; Academic Press: London, 1996.
2. Robinson, B. The Fischer Indole Synthesis; John Wiley and Sons: New York, 1982; ref 1, p 54-70.
3. (a) Gassman, P. G.; van Bergen, T. J.; Gilbert, D. P.; Cue, B. W., Jr. J. Am. Chem. Soc. 1974, 96, 5495.
4. (b) Sugasawa, T.; Adachi, M.; Sasakura, K.; Kitagawa, A. J. Org. Chem. 1979, 44, 578.
5. (c) Bartoli, G.; Bosco, M.; Dalpozzo, R.; Palmeri, G.; Marcantoni, E. J. Chem. Soc., Perkin Trans. 1 1991, 2757.
6. (d) Hwu, J. R.; Patel, H. V.; Lin, R. J.; Gray, M. O. J. Org. Chem. 1994, 59, 1577.
7. (a) Hegedus, L. S. Angew. Chem., Int. Ed. Engl. 1988, 27, 1113.
8. (b) Li, J. J. In Alkaloids: Chemical and Biological Perspectives; Pelletier, S. W., Ed.; Wiley: New York, 1999; Vol. 14, p 437.
9. (a) Larock, R. C.; Yum, E. K.; Refvik, M. D. J. Org. Chem. 1998, 63, 7652.
10. (b) Larock, R. C.; Yum, E. K. J. Am. Chem. Soc. 1991, 113, 6689.
11. (c) Arcadi, A.; Cacchi, S.; Marinelli, F. Tetrahedron Lett. 1992, 33, 3915.
12. (d) Cacchi, S.; Fabrizzi, G.; Marinelli, F.; Moro, L.; Pace, P. Synlett 1997, 1363.
13. (e) Soderberg, B. C.; Shriver, J. A. J. Org. Chem. 1997, 62, 5838.
14. (f) Tollari, S.; Cenini, S.; Crotti, C.; Gianella, E. J. Mol. Catal. 1994, 87, 203.
15. (g) Akazome, M.; Kondo, T.; Watanabe, Y. Chem. Lett. 1992, 769.
16. (h) Yamaguchi, M.; Arisawa, M.; Hirama, M. J. Chem. Soc., Chem. Commun. 1998, 1399.
17. (a) Srivastava, A.; Ma, Y.; Pankayatselvan, R.; Dinges, W.; Nicholas, K. M. J. Chem. Soc., Chem. Commun. 1992, 853.
18. (b) Srivastava, R. S.; Nicholas, K. M. Tetrahedron Lett. 1994, 8739.
19. (c) Srivastava, R. S.; Nicholas, K. M. J. Org. Chem. 1994, 59, 5365.
20. (d) Srivastava, R. S.; Khan, M. A.; Nicholas, K. M. J. Am. Chem. Soc. 1996, 118, 3311.
21. (e) Srivastava, R. S.; Nicholas, K. M. J. Chem. Soc., Chem. Commun. 1996, 2335.
22. (f) Srivastava, R. S.; Nicholas, K. M. J. Am. Chem. Soc. 1997, 119, 3302.
23. (a) Srivastava, R. S.; Nicholas, K. M. J. Chem. Soc., Chem. Commun. 1998, 2705.
24. (b) Kolel-Veetil, M. K.; Khan, M. A.; Nicholas, K. M. Organometallics 2000, 19, 3754.
25. Penoni, A.; Nicholas, K. M. J. Chem. Soc., Chem. Commun. In press.
26. (a) Cenini, S.; Ragaini, F. Catalytic Reductive Carbonylation of Organic Nitro Compounds; Kluwer Academic: Dordrecht, Netherlands, 1997.
27. (b) Tafesh, A. M.; Weiguny, J. Chem. Rev. 1996, 96, 2035.
28. Experimental Procedure. A stainless steel autoclave fitted with a glass liner and a magnetic spin bar was charged with catalyst (0.15 mmol), nitrosoarene (3 mmol), alkyne (12 mmol), and distilled solvent (benzene, 10 mL). In a well-ventilated fume hood the autoclave was purged with CO three times (CAUTION, toxic) and finally pressurized to 750 psi. The vessel was then heated to 170°C for 24 h. After cooling, the autoclave was vented in the fume hood, the solvent was removed by rotary evaporation, and the products were isolated by flash chromatography over silica gel. Product characterizational data are provided in Supporting Information.
29. -1. N-Hydroxyindoles, as found for 2, are typically unstable (see ref 12a for a review of N-hydroxyindoles) and subject to facile autoxidation (ref 13) and hydrogenolysis to indoles (ref 12a). An alternative formulation of 2a as 4-phenyl-1,2-benzooxazine is less consistent with the compound's high polarity and abundant (M - 1) MS ion.
30. (a) Somei, M. Heterocycles 1999, 50, 1157.
31. (b) Acheson, R. M.; Hunt, P. G.; Littlewood, D. M.; Murrer, B. A.; Rosenberg, H. E. J. Chem. Soc., Perkin Trans. 1 1978, 1117.
32. Berti, C.; Greci, L.; Poloni, M. J. Chem. Soc., Perkin Trans. 1 1981, 1610.
33. Galvinoxyl did largely suppress the formation of the major byproduct, azoxybenzene.
34. 2 was bubbled into the solution. After 5-6 h TLC analysis indicated complete consumption of 2 and clean formation of the corresponding indole; filtration to remove the catalyst and solvent evaporation provided the indole, which was pure by NMR analysis (see Supporting Information).
35. Zuman, P.; Shah, B. Chem. Rev. 1994, 94, 1621.
36. (a) Porta, F.; Prati, L. J. Mol. Catal. A 2000, 157, 123.
37. (b) Bosch, E.; Kochi, J. K. J. Org. Chem. 1994, 59, 5573.