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Multivariate statistical treatment of solvent effects in the photoreduction of CoIII(En)2(Br)(RC6H4NH2)2+ complexes in aqua-organic solvent media

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Abstract

Ultraviolet photolysis (λ = 254 nm) studies were carried out for a series of cobalt(III) complexes, CoIII(En)2(Br)(RC6H4NH2)2+, where R = m-OMe, p-F, H, m-Me, p-Me, p-OEt, and p-OMe, in various compositions of water-methanol/1,4-dioxane mixtures (0, 5, 10, 15, 20, 25, and 30 vol % organic cosolvent) at two different temperatures (287 and 300 K). The ligand-to-metal charge-transfer excited state produced in the excitation of the complex initially generated a solvent-caged {CoII; ligand radical} pair, which eventually undergoes recombination/separation into products. The quantum yield sharply increased from a mixture containing a lower mole fraction of organic cosolvent (x org) to higher one. In other words, when x org in the mixture increases, a steady increase in the quantum yield is observed. The quantum yield of CoIII(En)2(Br)(RC6H4NH2)2+ in various solvent mixtures is found to exhibit a linear (logΦCo(II) − 1/εr) dependence. This is consistent with solvation or solvent cage effect, which may be nonspecific, specific, or both. In order to throw light on these effects, a phenomenological model of solvent effects was applied. Therefore, the quantum yield values have been correlated statistically with some success containing different solvent parameters. The solvent parameters considered in this work are Grunwald-Winstein’s Y, Krygowski-Fawcett’s E N T and DN N along with Kamlet-Taft’s α, β, π* parameters. The regression model proposed is Y S = Y 0 + Σ ni = 1 a i X i , where YS is the solvent-dependent property (here logΦCo(II)) in a given solvent; Y 0 is the statistical quantity corresponding to the value of property in the reference solvent; X 1, X 2, X 3 … are explanatory variables, the solvent parameters, which can explain the various solvation effects on reactants/{CoII; ligand radical} pair, and a 1, a 2, a 3… etc., are the regression coefficients. The coefficient values can be quantified to measure the relative importance of solvent effects on the physicochemical quantity, that is, the photoreduction yields in the present investigation.

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References

  1. Ziegler, T., Chem. Rev., 1991, vol. 91, no. 5, p. 651.

    Article  CAS  Google Scholar 

  2. Katritzky, A.R., Fara, D.C., Yang, H., and Tamm, K., Chem. Rev., 2004, vol. 104, no. 1, p. 175.

    Article  CAS  Google Scholar 

  3. Sosa, C., Andzelm, J., Elkin, B.C., et al., J. Phys. Chem., 1992, vol. 96, no. 16, p. 6630.

    Article  CAS  Google Scholar 

  4. Hamra, O.Y., Slep, L.D., Olabe, J.A., and Estrin, D.A., Inorg. Chem., 1998, vol. 37, no. 8, p. 2033.

    Article  CAS  Google Scholar 

  5. Prow, W.F., Garmestani, S.K., and Farina, R.D., Inorg. Chem., 1981, vol. 20, no. 4, p. 1297.

    Article  CAS  Google Scholar 

  6. Anbalagan, K., Geethalakshmi, T., and Poonkodi, S.P.R., J. Phys. Chem. A, 2003, vol. 107, no. 12, p. 1918.

    Article  CAS  Google Scholar 

  7. Anbalagan, K., Siva Illango, S., and Poonkodi, S.P.R., J. Chem. Res.(S), 2003, no. 3, p. 69.

  8. Anbalagan, K. and Poonkodi, S.P.R., Transition Met. Chem. (London), 2001, vol. 26, nos. 1–2, p. 212.

    Google Scholar 

  9. Karthikeyan, G., Anbalagan, K., and Elango, K.P., Transition Met. Chem. (London), 2002, vol. 27, no. 1, p. 52.

    Article  CAS  Google Scholar 

  10. Kuzniarska-Biernacka, I., Bartecki, A., and Kurzak, K., Polyhedron, 2003, vol. 22, p. 997.

    Article  CAS  Google Scholar 

  11. Amis, E.S., and Hinton, J.F., Solvent Effects of Chemical Phenomena, New York: Academic, 1973, vol. 1.

    Google Scholar 

  12. Fainberg, A.H. and Winstein, S., J. Am. Chem. Soc., 1956, vol. 78, no. 12, p. 2770.

    Article  CAS  Google Scholar 

  13. Reichardt, C., Solvents and Solvent Effects in Organic Chemistry, Weinheim: VCH, 1988.

    Google Scholar 

  14. Marcus, Y., Ion Solvation, Chichester (UK): Wiley, 1985.

    Google Scholar 

  15. Dawber, J.G., Ward, J., and Wialliams, R.A., J. Chem. Soc., Faraday Trans. 1, 1988, vol. 84, no. 3, p. 713.

    Article  CAS  Google Scholar 

  16. Krygowski, T.M., Wrona, P.K., and Zielkowska, U., Tetrahedron, 1985, vol. 41, no. 20, p. 4519.

    Article  CAS  Google Scholar 

  17. Kamlet, M.J., Abboud, J-L.M., Abraham, M.H., and Taft, R.W., J. Org. Chem., 1983, vol. 48, no. 17, p. 2877.

    Article  CAS  Google Scholar 

  18. Karthikeyan, G., Anbalagan, K., and Elango, K.P., Russ. J. Coord. Chem., 2000, vol. 26, no. 8, p. 592.

    Google Scholar 

  19. Anbalagan, K., Danishad, K.A., and Poonkodi, S.P.R., Indian J. Chem., Sect. A: Inorg., Bioinorg., Phys., Theor. Anal. Chem., 2003, vol. 42, p. 1040.

    Google Scholar 

  20. Karthikeyan, G., Anbalagan, K., and Elango, K.P., Transition Met. Chem. (London), 2000, vol. 25, no. 2, p. 213.

    Article  CAS  Google Scholar 

  21. Bailer, J.C. and Rollinson, C.L., Inorg. Synth., 1946, vol. 22, p. 222.

    Google Scholar 

  22. Bailer, J.C. and Clapp, L.B., J. Am. Chem. Soc., 1945, vol. 67, no. 2, p. 171.

    Article  Google Scholar 

  23. Kiston, R.E., Anal. Chem., 1950, vol. 22, no. 5, p. 664.

    Article  Google Scholar 

  24. Calvert, J.G. and Pitts, J.N., Photochemistry, New York: Wiley, 1966.

    Google Scholar 

  25. Shorter, J., Correlation Analysis of Organic Reactivity, New York: Wiley, 1982.

    Google Scholar 

  26. Charton, M., J. Org. Chem., 1975, vol. 40, no. 4, p. 407.

    Article  CAS  Google Scholar 

  27. Anbalagan, K. and Poonkodi, S.P.R., The Third Intern. Symp. on Recent Trends in Photochemical Sciences, Trivandrum (India), 2004.

  28. Garcia, C.G., de Lima, J.F., and Iha, N.Y.M., Coord. Chem. Rev., 2000, vol. 196, no. 1, p. 219.

    Article  CAS  Google Scholar 

  29. Weit, S.K., Ferraudi, G., Grutsch, P.A., and Kutal, C., Coord. Chem. Rev., 1993, vol. 128, nos. 1–2, p. 225.

    Article  CAS  Google Scholar 

  30. Endicott, J.F., Ferraudi, G.J., and Barber, J.R., J. Phys. Chem., 1975, vol. 79, no. 6, p. 630.

    Article  CAS  Google Scholar 

  31. Weit, S.K., and Kutal, C., Inorg. Chem., 1990, vol. 29, no. 8, p. 1455.

    Article  CAS  Google Scholar 

  32. Ferraudi, G.J., Endicott, J.F., and Barber, J.R., J. Am. Chem. Soc., 1975, vol. 97, no. 22, p. 6406.

    Article  CAS  Google Scholar 

  33. Laidler, K.J. and Erying, H., Ann. N. Y. Acad. Sci., 1940, vol. 39, p. 303.

    CAS  Google Scholar 

  34. Ingold, C.K., Structure and Mechanism in Organic Chemistry, Ithaca-New York: Cornell Univ. Press, 1953.

    Google Scholar 

  35. Koo, I.S., Yang, K., Kang, K., et al., J. Chem. Soc., Perkin Trans., 1998, no. 5, p. 1179.

  36. Bentley, T.W. and Llewellyn, G., Prog. Phys. Org. Chem., 1990, vol. 17, p. 121.

    CAS  Google Scholar 

  37. Bentley, T.W. and Carter, G.E., J. Am. Chem. Soc., 1982, vol. 104, no. 21, p. 5741.

    Article  CAS  Google Scholar 

  38. Fawcett, W.R. and Krygowski, T.M., Aust. J. Chem., 1975, vol. 28, p. 2115.

    Article  CAS  Google Scholar 

  39. Krygowski, T.M. and Fawcett, W.R., J. Am. Chem. Soc., 1975, vol. 97, no. 8, p. 2143.

    Article  CAS  Google Scholar 

  40. Reichardt, C., Angew. Chem. Int. Ed. Engl., 1979, vol. 18, p. 98.

    Article  Google Scholar 

  41. Cusumano, M. and Langford, C.H., Inorg. Chem., 1978, vol. 17, no. 8, p. 2222.

    Article  CAS  Google Scholar 

  42. Wells, C.F., J. Chem. Soc., Faraday Trans. 1, 1974, vol. 70, no. 1, p. 694.

    Article  CAS  Google Scholar 

  43. Clark, T., Henmann, M., van Eldik, R., and Meyerstein, D., Inorg. Chem., 2002, vol. 41, no. 11, p. 2927.

    Article  CAS  Google Scholar 

  44. Khoshtariya, D.E., Bajaj, H.C., Tregloan, P.A., and van Eldik, R., J. Phys. Chem. A, 2000, vol. 104, no. 23, p. 5535.

    Article  CAS  Google Scholar 

  45. Thomas, J.A., Hutchings, M.G., Jonrd, C.J., and McCleverty, J.A., Inorg. Chem., 1996, vol. 35, no. 2, p. 289.

    Article  CAS  Google Scholar 

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  1. Department of Chemistry, Gandhigram Rural Institute (Deemed University), Gandhigram, 624302, Tamilnadu, India

    K. Anbalagan

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Anbalagan, K. Multivariate statistical treatment of solvent effects in the photoreduction of CoIII(En)2(Br)(RC6H4NH2)2+ complexes in aqua-organic solvent media. Russ J Coord Chem 32, 364–373 (2006). https://doi.org/10.1134/S1070328406050095

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