New route to 2-cyanobenzothiazoles viaN-arylimino-1,2,3-dithiazoles †

Abstract

N-Arylimino-1,2,3-dithiazole derivatives 2 of 2-bromoanilines are converted in high yield into 2-cyanobenzothiazoles 3 by heating or, more rapidly, by focused microwave irradiation at atmospheric pressure, in pyridine containing cuprous iodide.

References

1. R. Appel, H. Janssen, M. Siray and F. Knoch, Chem. Ber., 1985, 118, 1632.
2. (a) T. Besson, K. Emayan and C. W. Rees, J. Chem. Soc., Perkin Trans. 1, 1995, 2097; (b) O. A. Rakitin, C. W. Rees and O. G. Vlasova, Tetrahedron Lett., 1996, 37, 4589; (c) T. Besson and C. W. Rees, J. Chem. Soc., Perkin Trans. 1, 1996, 2857; (d) C. W. Rees, D. G. Roe and V. Thiéry, Chem. Commun., 1996, 2775; (e) T. Besson, G. Guillaumet, C. Lamazzi and C. W. Rees, Synlett, 1997, 704.
3. (a) C. W. Rees, J. Heterocycl. Chem., 1992, 29, 639; (b) T. Besson and C. W. Rees, J. Chem. Soc., Perkin Trans. 1, 1995, 1659; (c) R. F. English, O. A. Rakitin, C. W. Rees and O. G. Vlasova, J. Chem. Soc., Perkin Trans. 1, 1997, 201.
4. V. Bénéteau, T. Besson and C. W. Rees, Synth. Commun., 1997, 27, 2275.
5. (a) R. Commarmot, R. Didenot and J. F. Gardais, Rhône-Poulenc/Prolabo, Patent 84/03496, 1984, Fr. Pat. FR 2560686, 1985; (b) P. Jacquault, Prolabo, Fr. Pat. FR 9116286, 1991.
6. G. P. Ellis and T. M. Romney-Alexander, Chem. Rev., 1987, 87, 779.
7. T. Besson, M. J. Dozias, J. Guillard, P. Jacquault, M. D. Legoy and C. W. Rees, Tetrahedron, 1998, 54, 6475 For reviews see: S. Caddick, Tetrahedron, 1995, 51, 10403; K. Bougrin, M. Soufiaoui, A. Loupy and P. Jacquault, New. J. Chem., 1995, 19, 213; S. A. Galema, Chem. Soc. Rev., 1997, 26, 233.