Journal of Atmospheric Chemistry

, Volume 52, Issue 2, pp 203–219 | Cite as

Laboratory Determination of the Carbon Kinetic Isotope Effects (KIEs) for Reactions of Methyl Halides with Various Nucleophiles in Solution

Article
Received:
Accepted:

Abstract

Large carbon kinetic isotope effects (KIEs) were measured for reactions of methyl bromide (MeBr), methyl chloride (MeCl), and methyl iodide (MeI) with various nucleophiles at 287 and 306 K in aqueous solutions. Rates of reaction of MeBr and MeI with H2O (neutral hydrolysis) or Cl− (halide substitution) were consistent with previous measurements. Hydrolysis rates increased with increasing temperature or pH (base hydrolysis). KIEs for hydrolysis were 51 ± 6%0 for MeBr and 38 ± 8%0 for MeI. Rates of halide substitution increased with increasing temperature and greater reactivity of the attacking nucleophile, with the fastest reaction being that of MeI with Br−. KIEs for halide substitution were independent of temperature but varied with the reactant methyl halide and the attacking nucleophile. KIEs were similar for MeBr substitution with Cl− and MeCl substitution with Br− (57 ± 5 and 60 ± 9%0, respectively). The KIE for halide exchange of MeI was lower overall (33 ± 8%0) and was greater for substitution with Br− (46 ± 6%0) than with Cl− (29 ± 6%0).

Keywords

abiotic fractionation kinetic isotope effects methyl halides 
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bill, M., Rhew, R. C., Weiss, R. F., and Goldstein, A. H., 2002a: Carbon isotope ratios of methyl bromide and methyl chloride emitted from a coastal salt marsh, Geophys. Res. Lett. 29(4),  doi:10.1029/2001GL012946
  2. Bill, M., Miller, L. G., and Goldstein, A. H., 2002b: Carbon isotope fractionation of methyl bromide during agricultural soil fumigations, Biogeochemistry 60, 181–190.CrossRefGoogle Scholar
  3. Bill, M., Conrad, M. E., and Goldstein, A. H., 2004: Stable carbon isotope composition of atmospheric methyl bromide, Geophys. Res. Lett. 31, L04109,  doi:10.1029/2003GL018639 CrossRefGoogle Scholar
  4. Blake, N. J., Blake D. R., Sive, B. B., Chen, T.-Y., Rowland, F. S., Collins Jr., J. E., Sachse, G. W., and Anderson, B. E., 1996: Biomass burning emissions and vertical distribution of atmospheric methyl halides and other reduced carbon gases in the South Atlantic region, J. Geophys. Res. 101, 24,151–24,164.Google Scholar
  5. Connell, T. L., Joye, S. B., Miller, L. G., and Oremland, R. S., 1997: Bacterial oxidation of methyl bromide in Mono Lake, California, Environ. Sci. and Technol. 31, 1489–1495.Google Scholar
  6. Elliott, S. and Rowland, F. S., 1993: Nucleophilic substitution rates and solubilities for methyl halides in seawater, Geophys. Res. Lett. 20, 1043–1046.Google Scholar
  7. Elliott, S. M. and Rowland, F. S., 1995: Methyl halide hydrolysis rates in natural waters, J. Atmos. Chem. 20, 229–236.CrossRefGoogle Scholar
  8. Gentile, I. A., Ferraris, L., Crespi, S., and Belligno, A., 1989: The degradation of methyl bromide in some natural fresh waters. Influence of temperature, pH, and light, Pestic. Sci. 25, 261–272.Google Scholar
  9. Hamilton, J. T. G., McRoberts, W. C., Keppler, F., Kalin, R. M., and Harper, D. B., 2003: Chloride methylation by plant pectin: An efficient environmentally significant process, Science 301, 206–209.Google Scholar
  10. Harper, D. B., 1985: Halomethane from halide ion – a highly efficient fungal conversion of environmental significance, Nature 315, 55–57.CrossRefGoogle Scholar
  11. Jeffers, P. M. and Wolfe, N. L., 1996: On the degradation of methyl bromide in sea water, Geophys. Res. Lett. 23, 1773–1776.CrossRefGoogle Scholar
  12. Jeffers, P. M., Wolfe, N. L., and Nzengung, V., 1998: Green plants: A terrestrial sink for atmospheric CH3Br, Geophys. Res. Lett. 25, 43–46.CrossRefGoogle Scholar
  13. Kalin, R. M., Hamilton, J. T. G., Harper, D. B., Miller, L. G., Lamb, C., Kennedy, J. T., Downey, A., McCauley, S., and Goldstein, A. H., 2001: Continuous flow stable isotope methods for study of δ13C fractionation during halomethane production and degradation, Rapid Commun. Mass Spectrom. 15, 357–363.CrossRefGoogle Scholar
  14. Keppler, F., Harper, D. B., Röckmann, T., Moore, R. M., and Hamilton, J. T. G., 2005: New insight into the atmospheric chloromethane budget gained using stable carbon isotope ratios, Atmos. Chem. Phys. Discuss. 5, 3899–3919.Google Scholar
  15. Khalil, M. A. K. and Rasmussen, R. A., 1999: Atmospheric methyl chloride, Atmos. Environ. 33, 1305–1321.Google Scholar
  16. King, D. B. and Saltzman, E. S., 1997: Removal of methyl bromide in coastal seawater: Chemical and biological rates, J. Geophys. Res. 102, 18,715–18,721.CrossRefGoogle Scholar
  17. Komatsu, D. D., Tsunogai, U., Yamaguchi, J., and Nakagawa, F., 2005: A selective unsaturated hydrocarbon subtraction technique for stable carbon isotopic analysis of atmospheric methyl chloride, methyl bromide, and C2–C5 saturated hydrocarbons using continuous-flow isotope ratio mass spectrometry, Rapid Commun. Mass Spectrom. 19, 477–483.CrossRefGoogle Scholar
  18. Lovelock, J. E., 1975: Natural halocarbons in the air and the sea, Nature 256, 193–194.CrossRefGoogle Scholar
  19. Manley, S. L. and Dastoor, M. N., 1987: Methyl halide (CH3 X) production from the giant kelp, Macorcystis, and estimates of global CH3 X production by kelp, Limnol. Oceanogr. 32, 709–715.Google Scholar
  20. McCauley, S. E., Goldstein, A. H., and DePaulo, D. J., 1999: An isotopic approach for understanding the CH3Br budget of the atmosphere, Proc. Natl. Acad. Sci. 96, 10006–10009.CrossRefGoogle Scholar
  21. Miller, L. G., Connell, T. L., Guidetti, J. R., and Oremland, R. S., 1997: Bacterial oxidation of methyl bromide in fumigated agricultural soils, Appl. Environ. Microbiol. 63, 4346–4354.Google Scholar
  22. Miller, L. G., Kalin, R. M., McCauley, S. E., Hamilton, J. T. G., Harper, D. B., Millet, D. B., Oremland, R. S., and Goldstein, A. H., 2001: Large carbon isotope fractionation associated with oxidation of methyl halides by methylotrophic bacteria, Proc. Natl. Acad. Sci. 98, 5833–5837.Google Scholar
  23. Miller, L. G., Warner, K. L., Baesman, S. M., Oremland, R. S., McDonald, I. R., Radajewski, S., and Murrell, J. C., 2004: Degradation of methyl bromide and methyl chloride in soil microcosms: Use of stable C isotope fractionation and stable isotope probing to identify reactions and the responsible microorganisms, Geochim. Cosmochim. Acta 68, 3271–3283.CrossRefGoogle Scholar
  24. Moelwyn-Hughes, E. A., 1938: The hydrolysis of methyl halides, Proc. Roy. Soc. A 164, 295–306.Google Scholar
  25. Montzka, S. A. et al., 2003: Controlled substances and other source gases. In Scientific Assessment of Ozone Depletion: 2002, World Meteorol. Org, Chapter 1: pp. 1.1 –1.83.Google Scholar
  26. Moore, R. M. and Zafiriou, O. C., 1994: Photochemical production of methyl iodide in seawater, J. Geophys. Res. 99, 16415–16420.Google Scholar
  27. Moore, R. M., Groszko, W., and Niven, S. J., 1996: Ocean-atmosphere exchange of methyl chloride: Results from NW Atlantic and Pacific Ocean studies, J. Geophys. Res. 101, 28,529-28,538.Google Scholar
  28. Oremland, R. S., Miller, L. G., Culbertson, C. W., Connell, T. L., and Jahnke, L., 1994: Degradation of methyl bromide by methanotrophic bacteria in cell suspensions and soils, Appl. Environ. Microbiol. 60, 3640–3646.Google Scholar
  29. Rasmussen, R. A., Khalil, M. A. K., Gunawardena, R., and Hoyt, S. D., 1982: Atmospheric methyl iodide (CH3I), J. Geophys. Res. 87, 3086–3090.CrossRefGoogle Scholar
  30. Redeker, K. R., Wang, N.-Y., Low, J. C., McMillan, A., Tyler, S. C., and Cicerone, R. J., 2000: Emissions of methyl halides and methane from rice paddies, Science 290, 966–969.CrossRefGoogle Scholar
  31. Rhew, R. C., Miller, B. R., and Weiss, R. F., 2000: Natural methyl bromide and methyl chloride emissions from coastal salt marshes, Nature 403, 292–295.CrossRefGoogle Scholar
  32. Rudolph, J., Lowe, D. C., Martin, R. J., and Clarkson, T. S., 1997: A novel method for compound specific determination of δ13C in volatile organic compounds at ppt levels in ambient air, Geophys. Res. Lett. 24, 659–662.CrossRefGoogle Scholar
  33. Shorter, J. H., Kolb, C. E., Crill, P. M., Kerwin, R. A., Talbot, R. W., Hines, M. E., and Harriss, R. C., 1995: Rapid degradation of atmospheric methyl bromide in soils, Nature 377, 717–719.CrossRefGoogle Scholar
  34. Swain, C. G. and Scott, C. B., 1953: Quantitative correlation of relative rates. Comparison of hydroxide ion with other nucleophilic reagents toward alkyl halides, esters, epoxides and acyl halides, J. Amer. Chem. Soc. 75, 141–147.Google Scholar
  35. Tait, V. K. and Moore, R. M., 1995: Methyl chloride (CH3Cl) production in phytoplankton cultures, Limnol. Oceanogr. 40, 189–195.CrossRefGoogle Scholar
  36. Thompson, A. E., Anderson, R. S., Rudolph, J., and Huang, L., 2002: Stable carbon isotope signatures of background tropospheric chloromethane and CFC113, Biogeochem. 60, 191–211.CrossRefGoogle Scholar
  37. Tokarczyk, R., Goodwin, K. D., and Saltzman, E. S., 2001: Methyl bromide loss rate constants in the North Pacific Ocean, Geophys. Res. Lett. 28, 4429–4432.CrossRefGoogle Scholar
  38. Tokarczyk, R., Saltzman, E. S., Moore, R. M., and Yvon-Lewis, S. A., 2003: Biological degradation of methyl chloride in coastal seawater, Global Biogeochem. Cycles 17, 1057,  doi:10.1029/2002GB001949 CrossRefGoogle Scholar
  39. Tsunogai, U., Yoshida, N., and Gamo, T., 1999: Carbon isotopic compositions of C2–C5 hydrocarbons and methyl chloride in urban, coastal, and maritime atmospheres over the western North Pacific, J. Geophys. Res. 104, 16,033–16,039.CrossRefGoogle Scholar
  40. Willi, A. V., 1977: Kinetic carbon and other isotope effects in cleavage and formation of bonds to carbon, Isot. Org. Chem. 3, 237–283.Google Scholar
  41. Yagi, K., Williams J., Wang N-Y, and Cicerone R. J., 1995: Atmospheric methyl bromide (CH3Br) from agricultural soil fumigations, Nature 267, 1979–1981.Google Scholar
  42. Yokouchi, Y., Ikeda, M., Inuzuka, Y., and Yukawa, T., 2002: Strong emission of methyl chloride from tropical plants. Nature 416, 163–165.CrossRefGoogle Scholar
  43. Yvon-Lewis, S. A. and Butler, J. H., 1997: The potential effect of oceanic biological degradation on the lifetime of atmospheric CH3Br, Geophys. Res. Lett. 24, 1227–1230.CrossRefGoogle Scholar
  44. Zafiriou, O. C., 1974: Photochemistry of halogens in the marine atmosphere, J. Geophys. Res. 79, 2730–2732.Google Scholar
  45. Zafiriou, O. C., 1975: Reaction of methyl halides with seawater and marine aerosols, J. Mar. Res. 33, 75–81.Google Scholar

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  1. 1.U.S. Geological SurveyUSA

Personalised recommendations