The reaction of N-methylbenzothiazole-2-selone with the interhalogens iodine monobromide and iodine monochloride

Abstract

Two 1∶1 interhalogen adducts of N-methylbenzothiazole-2-selone (mbts) have been prepared and crystallographically characterised: mbts·IBr (1) and mbts·ICl (2). Both exhibit the charge transfer ‘spoke’ structure consisting of a linear Se–I–X arrangement (X = Br or Cl) where d(C–Se) increases from that seen for mbts by 0.058(5) and 0.062(8) Å (1 and 2 respectively); d(C–N) decreases by 0.019(4) and 0.019(9) Å. This indicates electron density moves towards the Se–I–X moiety upon co-ordination, causing a partial positive charge to reside on the nitrogen atom. The I–X bond lengthens with respect to the unco-ordinated species for both molecules. The addition of two equivalents of ICl to mbts gave a dark purple material of stoichiometry C₈H₇Cl_2.9I_1.1NSSe 3; the fractional stoichiometry for iodine and chlorine may be indicative of ‘halogen scrambling’. An additional product from this reaction was examined crystallographically and found to consist of the ion pair [C₈H₇NSCl]⁺[ICl₂]^–4, i.e. the C–Se double bond has been completely cleaved and replaced by a C–Cl single bond. The positive charge is again supported mostly by the nitrogen atom; d(C–N) decreases to 1.294(10) Å indicating a double bond.

References

1. F. Cristiani, F. A. Devillanova, A. Diaz and G. Verani, J. Chem. Soc., Perkin Trans. 2, 1984, 1383.
2. M. Cau, F. Cristiani, F. A. Devillanova and G. Verani, J. Chem. Soc., Perkin Trans. 2, 1985, 749.
3. F. Cristiani, F. Demartin, F. A. Devillanova, F. Isaia, G. Saba and G. Verani, J. Chem. Soc., Dalton Trans., 1992, 3553.
4. F. Cristiani, F. A. Devillanova, F. Isaia, V. Lippolis and G. Verani, Inorg. Chem., 1994, 33, 6315.
5. F. Demartin, P. Deplano, F. A. Devillanova, F. Isaia, V. Lippolis and G. Verani, Inorg. Chem., 1993, 32, 3694.
6. F. Demartin, F. A. Devillanova, F. Isaia, V. Lippolis and G. Verani, Inorg. Chim. Acta, 1997, 255, 203.
7. F. Bigoli, A. M. Pellinghelli, P. Deplano, F. A. Devillanova, V. Lipolis, M. L. Mercuri and E. F. Trogu, Gazz. Chim. Ital., 1994, 124, 445.
8. S. Husebye, S. V. Lindeman and M. D. Rudd, Acta Crystallogr., Sect. C, 1997, 53, 809.
9. J. S. Rutherford and C. Calvo, Z. Kristallogr., 1969, 128, 229.
10. H. M. K. K. Pathirana, T. J. Weiss, J. H. Reibenspies, R. A. Zingaro and E. A. Meyers, Z. Kristallogr., 1994, 209, 697.
11. H. Hope, Acta Crystallogr., 1965, 18, 259.
12. T. Srikrishnan, Acta Crystallogr., Sect. C, 1988, 44, 290.
13. J. Nakayama, A. Mizumura, I. Akiyama, T. Nishio and I. Iida, Chem. Lett., 1994, 77.
14. S. M. Godfrey, C. A. McAuliffe, R. G. Pritchard and S. Sarwar, J. Chem. Soc., Dalton Trans., 1997, 3501.
15. S. M. Godfrey, C. A. McAuliffe, R. G. Pritchard and S. Sarwar, J. Chem. Soc., Dalton Trans., 1997, 1031.
16. C. Knobler and J. D. McCullough, Inorg. Chem., 1968, 7, 365.
17. S. M. Godfrey, S. L. Jackson, C. A. McAuliffe and R. G. Pritchard, J. Chem. Soc., Dalton Trans., 1997, 4499.
18. S. M. Godfrey, S. L. Jackson, C. A. McAuliffe and R. G. Pritchard, J. Chem. Soc., Dalton Trans., 1998, 4201.
19. S. M. Godfrey, S. L. Jackson, C. A. McAuliffe and R. G. Pritchard, unpublished results.
20. F. Bigoli, F. Demartin, P. Deplano, F. A. Devillanova, F. Isaia, V. Lippolis, M. L. Mercuri, M. A. Pellinghelli and E. F. Trogu, Inorg. Chem., 1996, 35, 3194.
21. C. K. Johnson, ORTEP II, Report ORNL-5138, Oak Ridge National Laboratory, Oak Ridge, TN, 1976.
22. Handbook of Chemistry and Physics, ed. D. R. Lide, CRC Press, Boca Raton, FL, 76th edn., 1995, ch. 9, part 10.
23. M. Miura, Y. Takanohashi, Y. Habata and S. Akabori, J. Chem. Soc., Perkin Trans. 1, 1995, 1719; Tetrahedron Lett., 1994, 35, 8213.
24. G. M. Sheldrick, SHELXTL 97, Programs for crystal structure analysis (release 97-2), Göttingen, 1998.