Oxyhalogen–sulfur chemistry Oxidation of 2-aminoethanethiolsulfuric acid by iodate in acidic medium

Abstract

The oxidation of 2-aminoethanethiolsulfuric acid, AETSA, by iodate has been studied in highly acidic media. The reaction is very slow and shows some clock-reaction characteristics in which iodine is formed after some induction period. The oxidation of AETSA involves the oxidation of only one of the sulfur atoms to SO₄^2-. The other sulfur atom remains attached to the carbon chain as a sulfonic acid (taurine). The stoichiometry of the reaction is: IO₃^-+H₂NCH₂CH₂ S–SO₃H+H₂O→ H₂NCH₂CH₂SO₃H+I^- +SO₄^2-+2H⁺. The reaction of I₂ and AETSA was found to be slow and autoinhibitory as the I^- formed combines with the remaining I₂ to form the relatively unreactive triiodide ion, I₃^-. The second-order rate constant for the reaction between I₂ and AETSA was determined as 16.7±2.3 M^-1 s^-1.

References

1. C. R. Chinake and R. H. Simoyi, J. Phys. Chem., 1996, 100, 1643.
2. E. Mambo and R. H. Simoyi, J. Phys. Chem., 1993, 97, 13662.
3. C. R. Chinake, E. Mambo and R. H. Simoyi, J. Phys. Chem., 1994, 95, 2908.
4. J. B. Jones, C. R. Chinake and R. H. Simoyi, J. Phys. Chem., 1995, 99, 1523.
5. S. Hashimoto and J. Sunamoto, Bull. Chem. Soc. Jpn., 1966, 39, 1207.
6. Y. Luo, M. Orban, K. Kustin and I. R. Epstein, J. Am. Chem. Soc., 1989, 111, 4541.
7. I. R. Wilson and G. M. Harris, J. Am. Chem. Soc., 1960, 82, 4515.
8. I. R. Wilson and G. M. Harris, J. Am. Chem. Soc., 1961, 84, 1101.
9. M. R. Hoffman, Environ. Eng. Sci., 1977, 11, 61.
10. R. J. Field, E. Koros and R. M. Noyes, J. Am. Chem. Soc., 1972, 94, 8649.
11. R. M. Noyes, Ber. Bunsen-Ges. Phys. Chem., 1980, 84, 295.
12. B. P. Belousov, Sb. Ref. Radiat. Med., 1959, 145, 1958.
13. A. M. Zhabotinsky, Dokl. Akad. Nauk SSSR., 1959, 157, 392.
14. W. C. Bray, J. Am. Chem. Soc., 1921, 43, 1262.
15. G. Nicolis and J. Portnow, Chem. Rev., 1973, 73, 371.
16. T. C. Briggs and W. C. Rauscher, J. Chem. Educ., 1973, 50, 496.
17. R. M. Noyes, J. Am. Chem. Soc., 1980, 102, 4644.
18. R. J. Field and R. M. Noyes, J. Chem. Phys., 1974, 60, 1877.
19. D. Banard, J. Chem. Soc., 1957, 4675.
20. G. Rabai and M. Beck, J. Chem. Soc., Dalton Trans., 1985, 1669.
21. S. J. Dushman, J. Phys. Chem., 1904, 8, 453.
22. A. D. Autrey and R. E. Connick, J. Am. Chem. Soc., 1953, 73, 1842.
23. D. A. Skoog and D. M. West, Analytical Chemistry: An Introduction, Saunders College Publishing, San Francisco 4th edn., 1986, p. 83.
24. H. Landolt, Ber. Dtsch. Chem. Ges., 1886, 19, 1313.
25. D. C. Harris, Quantitative Chemical Analysis, W. H. Freeman and Co., San Francisco, 1982, p. 384.
26. P. Soupart, in Amino Acid Pools, ed. J. T. Holden, Elsevier, New York, 1962, pp. 220–262.
27. J. G. Jacobson and L. H. Smith, Physiol. Rev., 1968, 48, 424.
28. In the oxidation of thiourea by Br₂(aq), for example, an increase in the reductant concentration (thiourea) increased the induction period, see R. H. Simoyi and I. R. Epstein, J. Phys. Chem., 1987, 91, 5124.
29. R. M. Noyes, L. V. Kalachev and R. J. Field, J. Phys. Chem., 1995, 99, 3514.
30. M. Eigen and K. Kustin, J. Am. Chem. Soc., 1962, 84, 1355.
31. T. R. Thomas and D. T. Pence, J. Inorg. Nucl. Chem., 1980, 42, 183.
32. S. D. Furrow and R. M. Noyes, J. Am. Chem. Soc., 1982, 104, 38.
33. L. Treindl and R. M. Noyes, J. Phys. Chem., 1993, 97, 11354.
34. M.-F. Ruasse, J. Aubard, B. Galland and A. Adenier, J. Chem. Phys., 1986, 90, 4382.
35. P. Kaps and P. Rentrop, Numer. Math., 1979, 23, 55.