Secondary steric effects in S_NAr of thiophenes: a coordinate kinetic, thermodynamic, UV–VIS, crystallographic and ab initio study

Abstract

The reactivity of some dinitro-benzene and -thiophene derivatives with piperidine and sodium benzenethiolate has been examined giving evidence that benzenes show large and thiophenes show small kinetic secondary steric effects, respectively. The acid dissociation reaction and the UV–VIS spectra of some nitrothiophenamines have also been studied. The crystal structure and the absolute conformation of 2-iodo-3,5-dinitrothiophene and of 2-iodo-4-methyl-3,5-dinitrothiophene have been determined. For different conformations of the analogous chlorodinitro derivatives in the thiophene and benzene series, ab initio energy calculations have been performed. The results collected show that steric strain among adjacent groups affects the benzene and thiophene compounds and the kinetic, thermodynamic and spectroscopic properties of the molecules examined differently. Differences in geometry of the two aromatic rings and then in rotation of nitro groups with respect to the rings themselves as well as differences along reaction coordinates (essentially depending on hybridation changes) are used to explain the above data.

References

1. (a) H. Lindemann and A. Pabst, Annalen, 1928, 462, 24; (b) B. Capon and N. B. Chapman, J. Chem. Soc., 1957, 600 and references therein.
2. A. Mugnoli, D. Spinelli, G. Consiglio and R. Noto, Cryst. Struct. Commun., 1981, 10, 983.
3. K. J. Watson, Nature, 1960, 188, 1102; E. M. Gopalakrishna, Acta Crystallogr., Sect. A, 1969, 25, S150; H. Takazawa, S. Ohba and Y. Saito, Acta Crystallogr., Sect. B, 1989, 45, 432; S. Sharma, N. Weiden and A. Weiss, J. Chem. Phys., 1989, 90, 483; A. Wilkins, R. W. H. Small and J. T. Gleghorn, Acta Crystallogr., Sect. B, 1990, 46, 823 In the last paper a less stable beta form, with a rotation angle as high as 69°, is also described.
4. (a) D. Spinelli, C. Dell'Erba and G. Guanti, J. Heterocycl. Chem., 1968, 5, 323; (b) D. Spinelli, G. Consiglio and A. Corrao, J. Chem. Soc., Perkin Trans. 2, 1972, 1866; (c) D. Spinelli, G. Consiglio, R. Noto and A. Corrao, J. Chem. Soc., Perkin Trans. 2, 1974, 1632; (d) D. Spinelli and G. Consiglio, J. Chem. Soc., Perkin Trans. 2, 1975, 1388; (e) C. Arnone, G. Consiglio, S. Gronowitz, B. Maltesson, A.-B. Hörnfeldt, R. Noto and D. Spinelli, Chemica Scripta, 1978–1979, 13, 130; (f) G. Consiglio, C. Arnone, D. Spinelli, R. Noto, V. Frenna and S. Fisichella, J. Chem. Soc., Perkin Trans. 2, 1985, 519; (g) G. Consiglio, C. Arnone, D. Spinelli, R. Noto, V. Frenna, S. Fisichella and F. A. Bottino, J. Chem. Soc., Perkin Trans. 2, 1985, 523.
5. (a) C. H. Rochester, Acidity Functions, Academic Press, London, 1970; E. M. Arnett and G. W. Mach, J. Am. Chem. Soc., 1964, 86, 2671; K. Yates, H. Wai, G. Welch and R. A. McClelland, J. Am. Chem. Soc., 1973, 95, 5960; (b) N. C. Marziano, G. M. Cimino and R. Passerini, J. Chem. Soc., Perkin Trans. 2, 1975, 341; R. Cox and K. Yates, J. Am. Chem. Soc., 1978, 100, 3861; (c) P. De Maria, R. Noto, G. Consiglio and D. Spinelli, J. Chem. Soc., Perkin Trans. 2, 1989, 791.
6. σ_m Values for alkyl groups range between –20.06 and –20.09 (e.g. see O. Exner, Correlation Analysis of Chemical Data, p. 61, Plenum Press, New York, 1988).
7. G. Consiglio, D. Spinelli, S. Gronowitz, A.-B. Hörnfeldt, B. Maltesson and R. Noto, J. Chem. Soc., Perkin Trans. 2, 1982, 625.
8. S. Gronowitz, Arkiv Kemi, 1958, 13, 295; D. Spinelli, G. Guanti and C. Dell'Erba, J. Chem. Soc., Perkin Trans. 2, 1972, 441; S. Gronowitz, I. Johnson and A.-B. Hörnfeldt, Chemica Scripta, 1975, 7, 76, 211; D. Spinelli, R. Noto and G. Consiglio, J. Chem. Soc., Perkin Trans. 2, 1976, 747; D. Spinelli, R. Noto, G. Consiglio and A. Storace, J. Chem. Soc., Perkin Trans. 2, 1976, 1805; G. Consiglio, S. Gronowitz, A.-B. Hörnfeldt, R. Noto, K. Petterson and D. Spinelli, Chemica Scripta, 1978–1979, 13, 20; G. Consiglio, S. Gronowitz, A.-B. Hörnfeldt, R. Noto and D. Spinelli, Chemica Scripta, 1980, 15, 49; G. Consiglio, D. Spinelli, S. Fisichella, G. Alberghina and R. Noto, J. Chem. Soc., Perkin Trans. 2, 1980, 1153; R. Noto, S. Buscemi, G. Consiglio and D. Spinelli, J. Heterocycl. Chem., 1981, 18, 735; G. Consiglio, D. Spinelli, S. Gronowitz, A.-B. Hörnfeldt and R. Noto, Chemica Scripta, 1982, 19, 46.
9. C. K. Johnson, ORTEP, Report ORNL-3794, Oak Ridge National Laboratory, Tennessee, 1965.
10. A. Mugnoli, D. Spinelli, G. Consiglio and R. Noto, J. Heterocycl. Chem., 1988, 25, 177.
11. A. Mugnoli, M. Novi, G. Guanti and C. Dell'Erba, Cryst. Struct. Commun., 1978, 7, 703.
12. U. Folli, D. Iarossi, A. Mucci, A. Musatti, M. Nardelli, L. Schenetti and F. Taddei, J. Mol. Struct., 1991, 246, 99.
13. D. J. A. De Ridder and H. Schenk, Acta Crystallogr., Sect. B, 1995, 51, 221.
14. F. H. Allen, O. Kennard and R. Taylor, Acc. Chem. Res., 1983, 16, 146.
15. M. J. Frisch, G. W. Trucks, M. Head-Gordon, P. M. W. Gill, M. W. Wong, J. B. Foresman, B. G. Johnson, H. B. Schlegel, M. A. Robb, E. S. Replogle, R. Gomperts, J. L. Andres, K. Raghavachari, J. S. Binkley, C. Gonzalez, R. L. Martin, D. J. Fox, D. J. Defrees, J. Baker, J. J. P. Stewart and J. A. Pople, GAUSSIAN92, Revision C.4. Gaussian, Inc., Pittsburgh, PA, 1992.
16. D. Spinelli, C. Dell'Erba and A. Salvemini, Ann. Chim. (Rome), 1962, 52, 1156 and references therein.
17. D. Spinelli, G. Consiglio, R. Noto and A. Corrao, J. Chem. Soc., Perkin Trans. 2, 1974, 1632.
18. R. W. Bost, J. O. Turner and R. Norton, J. Am. Chem. Soc., 1932, 54, 1985.
19. D. Spinelli, C. Dell'Erba and G. Guanti, Ann. Chim. (Rome), 1965, 55, 1252.
20. L. Chierici, C. Dell'Erba and D. Spinelli, Ann. Chim. (Rome), 1965, 55, 1069.
21. J. F. Bunnett and N. Sbarbati Nudelmann, J. Org. Chem., 1969, 34, 2038.
22. A. C. T. North, D. C. Phillips and F. S. Mathews, Acta Crystallogr., Sect. A, 1968, 24, 351.
23. G. M. Sheldrick, SHELXL93, Program for Refinement of Crystal Structures, University of Göttingen, 1993.
24. H. D. Flack, Acta Crystallogr., Sect. A, 1983, 39, 876.
25. P. J. Jones, Acta Crystallogr., Sect. A, 1986, 42, 57.
26. M. Nardelli, Comput. Chem., 1983, 7, 95.