DOI QR코드

DOI QR Code

Dephosphorylation of Isopropyl phenyl-4-nitrophenylphosphinate (IPNPIN) onto 2-Alkylbenzimidazolide Anion in CTABr Micellar Solution

CTABr 미셀 용액속에서 2-Alkylbenzimidazole 음이온에 의해 추진되는 Isopropyl phenyl-4-nitrophenyl phosphinate(IPNPIN)의 탈인산화반응

Kim, Jeung-Bea
김정배

  • Received : 2012.01.12
  • Accepted : 2012.04.18
  • Published : 2012.05.31

Abstract

This study is mainly focused on micellar effect of cetyltrimethyl ammonium bromide(CTABr) solution including alkylbenzimidazole(R-BI) on dephosphorylation of isopropyl-4-nitrophenylphosphinate(IPNPIN) in carbonate buffer(pH 10.7). The reactions of IPNPIN with R-$BI^{\ominus}$ are strongly catalyzed by the micelles of CTABr. Dephosphorylation of IPNPIN is accelerated by $BI^{\ominus}$ ion in $10^{-2}$ M carbonate buffer(pH 10.7) of $4{\times}10^{-3}$ M CTABr solution up to 89 times as compared with the reaction in carbonate buffer by no benzimidazole(BI) solution of $4{\times}10^{-3}$ M CTABr. The value of pseudo first order rate constant($k_{\Psi}$) of the reaction in CTABr solution reached a maximum rate constant increasing micelle concentration. Such rate maxima are typical of micellar catalyzed bimolecular reactions. The reaction mediated by R-$BI^{\ominus}$ in micellar solutions are obviously slower than those by $BI^{\ominus}$, and the reaction rate were decreased with increase of lengths of alkyl groups. It seems due to steric effect of alkyl groups of R-$BI^{\ominus}$ in Stern layer of micellar solution. The surfactant reagent, CTABr, strongly catalyzes the reaction of IPNPIN with R-BI and its anion(R-$BI^{\ominus}$) in carbonate buffer(pH 10.7). For example, $4{\times}10^{-3}$ M CTABr in $1{\times}10^{-4}$ M BI solution increase the rate constant($k_{\Psi}=98.5{\times}10^{-3}\;sec^{-1}$) of the dephosphorylation by a factor ca.25, when compared with reaction($k_{\Psi}=3.9{\times}10^{-4}\;sec^{-1}$) in $1{\times}10^{-4}$ M BI solution(without CTABr). And no CTABr solution, in $1{\times}10^{-4}$ M BI solution increase the rate constant($k_{\Psi}=3.9{\times}10^{-4}\;sec^{-1}$) of the dephosphorylation by a factor ca.39, when compared with reaction ($k_{\Psi}=1.0{\times}10^{-5}\;sec^{-1}$) in water solution(without BI). This predicts that the reactivities of R-$BI^{\ominus}$ in the micellar pseudophase are much smaller than that of $BI^{\ominus}$. Due to the hydrophobicity and steric effect of alkyl group substituents, these groups would penetrate into the core of the micelle for stabilization by van der Waals interaction with long alkyl groups of CTABr.

Keywords

CTABr;Micellar effect;Alkylbenzimidazole;Dephosphorylation

References

  1. Al-Lohedan, H., Bunton, C. A., Mhala, M. M., 1982, Micellar effects upon spontaneous hydrolyses and their relation to mechanism, J. Amer. Chem. Soc., 104, 6654-6660. https://doi.org/10.1021/ja00388a030
  2. Blatt, A. H., 1943, Organic Synthesis, Collective vol II, 65.
  3. Bunton, C. A., Cerichelli, G., Ihara, Y., Sepulveda, L., 1979, Micellar catalysis and reactant incorporation in dephosphorylation and nucleophilic substitution, J. Amer. Chem. Soc., 101, 2429-2435. https://doi.org/10.1021/ja00503a032
  4. Bunton, C. A., Hong, Y. S., Romsted, L. S., Quan, C., 1981, Catalysis by hydrophobic tetraalkyl ammonium ions; Dephosphorylation of p-nitrophenyl diphenyl phosphate, J. Amer. Chem. Soc., 103, 5788-5794. https://doi.org/10.1021/ja00409a029
  5. Bunton, C. A., Debuzzaccarini, F., Hamed, F. H., 1983, Dephosphorylation in cationic micelles and microemulsions; Effects of added alcohols, J. Org. Chem., 48, 2457-2461. https://doi.org/10.1021/jo00163a003
  6. Bunton, C. A., Moffatt, J. R., 1985, Micellar reactions of hydrophilic ions; A coulombic model, J. Phys. Chem., 89(20), 4166-4169. https://doi.org/10.1021/j100266a003
  7. Bunton, C. A., Cuenca, A., 1987, Abnormal micellar effects on reactions of azide and N-alkyl-2-bromopyridinium ions, J. Org. Chem., 52(5), 901-907. https://doi.org/10.1021/jo00381a032
  8. Bunton, C. A., Mhala, M. M., Moffatt, J. R., 1989, Nucleophilic reactions in zwitterionic micelles of amine oxide or betaine sulfonate surfactants, J. Phys. Chem., 93(2), 854-858. https://doi.org/10.1021/j100339a061
  9. Bunton, C. A., 1997, Reactivity in aqueous association colloids. Descriptive utility of the pseudophase model, J. Molecular Liquids, 72, 231-249. https://doi.org/10.1016/S0167-7322(97)00040-8
  10. Cook, R. D., Diebert, C. E., Schwarz, W., Turley, P. C., Haake, P., 1973, Mechanism of nucleophilic displacement at phosphorus in the alkaline hydrolysis of phosphinate esters, J. Amer. Chem. Soc., 95, 8088-8096. https://doi.org/10.1021/ja00805a023
  11. Dekeijzer, A. H., Koole, L. H., Van der Hofstad, W. J. M., Buckrate, H. M., 1988, Enhancement of nucleophilic substitution reactions in phosphate esters; Influence of conformational transmission on the rate of solvolysis in alkyl diphenylphosphinates, J. Org. Chem., 54, 1453-1456.
  12. Fendler, E. J., 1966, Reaction mechanism in phosphate ester hydrolysis, John Wiley, 65-89.
  13. Fendler, J. H., Fendler, E. J., 1975, Catalysis in micellar and macromolecular system, Academic press, 4th. ed., New York, 30-47.
  14. Foroudian, H. J., Gillitt N. D., Bunton, C. A., 2002, Effects of nonionic micelles on dephosphorylation and aromatic nucleophilic substitution, J. Colloid Interf. Sci., 250, 230-237. https://doi.org/10.1006/jcis.2002.8306
  15. Hartly, G. S., 1936, Aqueous solution of paraffin chain salt, Herman Paris. press, 125-258.
  16. Hong, Y. S., Park, C. S., Kim, J. B., 1984, Chemical reactions in surfactant solution(I). Substituent effects of 2-alkylbenzimidazolide ion on dephosphorylation in CTABr solution, J. Kor. Chem. Soc., 29(5), 522-532.
  17. Kim, J. B., Kim, H. Y., 2004, Effect of $OH^{\Theta}$ and o-iodosobenzoate ions on dephosphorylation of organo phosphororus ester in CTAX micelle, J. Environ. Sci., 14(2), 241-249.
  18. Kim, J. B., 2005, Dephosphorylation of an organic phosphinate by nucleophile in anionic and cationic micellar solutions, J. Environ. Sci., 15(5), 485-491.
  19. Maximiano, F. A., Chaimovich, H, Cuccovia, I. M., 2006, Decarboxylation of 6-nitrobenzisoxazole-3-carboxylate in mixed micelles of zwitterionic and positively charged surfactants, Langmuir, 22, 8050-8055. https://doi.org/10.1021/la061042p
  20. McBain, J. W., 1913, Micellar formation of aqueous solution, Trans. Faraday Soc., 9, 99-112.
  21. Quina, F. H., Chaimovich, H., 1979, Ion exchange in micellar solutions 1; Conceptual framework for ion exchange in micellar solutions, J. Phys. Chem., 83(14), 1844-1850. https://doi.org/10.1021/j100477a010
  22. Romsted, I. R., Cordes, E. H., 1968, Secondary valence force catalysis.VII. Catalysis of hydrolysis of p-nitrophenyl hexanoate by micelle-forming cationic detergents, J. Amer. Chem. Soc., 90, 4404-4409. https://doi.org/10.1021/ja01018a036
  23. Perrin, D. D., Dempsey, B., 1974, Buffers for pH and metal ion control, Champman and Hall(London), 5.
  24. Santiago, J. Y., Nicholas, D. G., Bunton, C. A., 2004, Examination of the pseudophase model of monomer-micelle interconversion in cetylpyridinium chloride, J. Colloid Interf. Sci., 281, 482-487.