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A diffuse reflectance comparative study of benzil inclusion within microcrystalline cellulose and β-cyclodextrin

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Abstract

Diffuse reflectance and laser-induced techniques were used to study photochemical and photophysical processes of benzil adsorbed on two solid powdered supports, microcrystalline cellulose and β-cyclodextrin. In both substrates, a distribution of ground-state benzil conformers exists, largely dominated by skew conformations where the carbonyl groups are twisted one to the other. Room temperature phosphorescence was observed in air-equilibrated samples in both cases. The decay times vary greatly and the largest lifetime was obtained for benzil/β-cyclodextrin, showing that this host’s cavity accommodates benzil well, enhancing its room temperature phosphorescence. Triplet–triplet absorption of benzil entrapped in cellulose was detected and benzil ketyl radical formation also occurred. With benzil included into β-cyclodextrin, and following laser excitation, benzoyl radicals were detected on the millisecond timescale. Product analysis and identification of laser-irradiated benzil samples in the two hosts clearly showed that the main degradation photoproducts were benzoic acid and benzaldehyde. The main differences were a larger benzoic acid/benzaldehyde ratio in the case of cellulose and the formation of benzyl alcohol in this support.

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References

  1. L. F. Vieira Ferreira, Fotoquímica de corantes e outras moléculas orgânicas em superfícies, Química, 1999, 72, 28–46.

    Google Scholar 

  2. A. M. Botelho do Rego and L. F. Vieira Ferreira, in Handbook of Surfaces and Interfaces of Materials, ed. H. S. Nalwa, Academic Press, New York, 2001, vol. 2, ch. 7, pp. 275–313.

  3. F. Wilkinson and G. P. Kelly, in Photochemistry on Solid Surfaces, ed. M. Anpo and T. Matsuara, Elsevier, Amsterdam, 1989. pp. 31–47.

  4. F. Wilkinson and G. P. Kelly, in Handbook of Organic Photochemistry, ed. J. C. Scaiano, CRC Press, Boca Raton, 1989, vol. 1, ch. 12, pp. 293–314.

  5. L. F. Vieira Ferreira, I. Ferreira Machado, A. S. Oliveira, M. R. Vieira Ferreira, J. P. Da Silva, J. C. Moreira, A diffuse reflectance comparative study of benzil inclusion within p-tert-butylcalix[n]arenes (n = 4, 6 and 8) and silicalite, J. Phys. Chem. B, 2002, 106, 12584–12593.

    Article  Google Scholar 

  6. L. F. Vieira Ferreira, M. R. Vieira Ferreira, A. S. Oliveira, J. C. Moreira, Potentialities of diffuse reflectance laser-induced techniques in solid phase: a comparative study of benzophenone inclusion within p-tert-butylcalixarenes, silicalite and microcrystalline cellulose, J. Photochem. Photobiol., A, 2002, 153, 11–18.

    Article  Google Scholar 

  7. L. F. Vieira Ferreira, M. R. Vieira Ferreira, A. S. Oliveira, T. J. F. Branco, J. V. Prata, J. C. Moreira, Diffuse reflectance studies of ß-phenylpropiophenone and benzophenone inclusion complexes with calix[4], [6] and [8]arenes, Phys. Chem. Chem. Phys., 2002, 4, 204–210.

    Article  CAS  Google Scholar 

  8. L. F. Vieira Ferreira, J. C. Netto-Ferreira, I. Khmelinskii, A. R. Garcia, S. M. B. Costa, Photochemistry on surfaces: matrix isolation mechanisms for study of interactions of benzophenone adsorbed on microcrystalline cellulose investigated by diffuse reflectance and luminescence techniques, Langmuir, 1995, 11, 231–236.

    Article  Google Scholar 

  9. L. F. Vieira Ferreira, M. R. Freixo, A. R. Garcia, F. Wilkinson, Photochemistry on surfaces: fluorescence quantum yield determination of dyes adsorbed on microcrystalline cellulose, J. Chem. Soc., Faraday Trans., 1992, 88, 15–22.

    Article  CAS  Google Scholar 

  10. L. F. Vieira Ferreira, A. R. Garcia, M. F. Freixo, S. M. B. Costa, Photochemistry on surfaces: the solvent-matrix effect on the swelling of cellulose. An emission and absorption study of adsorbed auramine-O, J. Chem. Soc., Faraday Trans., 1993, 89, 1937–1944.

    Article  CAS  Google Scholar 

  11. J. P. Da Silva, L. F. Vieira Ferreira, A. M. Da Silva, A. S. Oliveira, A comparative study of the photophysics and photochemistry of 4-chlorophenol adsorbed on silicalite and ß-cyclodextrin, J. Photochem. Photobiol., A, 2002, 151, 157–164.

    Article  Google Scholar 

  12. L. F. Vieira Ferreira, A. S. Oliveira and J. C. Netto-Ferreira, in Fluorescence Microscopy and Fluorescent Probes 3, ed. A. Kotyc, Espero Publishing, Prague, 1999, pp. 199–208.

  13. L. F. Vieira Ferreira, M. J. Lemos, M. J. Reis, A. M. Botelho do Rego, UV/Vis absorption and luminescence and X-ray photoelectron spectroscopic studies of rhodamine dyes adsorbed onto different pore size silicas, Langmuir, 2000, 16, 5673–5680.

    Article  CAS  Google Scholar 

  14. D. J. Morantz, A. J. C. Wright, Structures of the excited states of benzil and related dicarbonyl molecules, J. Chem. Phys., 1971, 54, 692–697.

    Article  CAS  Google Scholar 

  15. R. Dutta, M. Chowdhury, Study of the magnetic field dependent behaviour of radicals generated photochemically from benzil in micellar media, J. Photochem. Photobiol., A, 1990, 55, 197–207.

    Article  CAS  Google Scholar 

  16. K. Bhattacharya, M. Chowdhury, Solvent shift and excited state geometries of benzil, J. Photochem., 1986, 33, 61–65.

    Article  Google Scholar 

  17. G. K. Das Mohapatra, J. Bhattacharya, J. Bandopadhyay, S. C. Bera, Flash phololysis of benzils, J. Photochem. Photobiol., A, 1987, 40, 47–58.

    Google Scholar 

  18. S. C. Bera, R. Mukherjee, M. Chowdhury, Spectra of benzil, J. Chem. Phys., 1969, 51, 754–761.

    Article  CAS  Google Scholar 

  19. T. Okutsu, M. Ooyama, K. Tani, H. Hiratsuka, A. Kawai, K. Obi, Kinetic study on the spin polarization switching of benzil in the presence of triethylamine, J. Phys. Chem. A, 2001, 105, 3741–3744.

    Article  CAS  Google Scholar 

  20. R. W. Fessenden, P. M. Carton, H. Shimamori, J. C. Scaiano, Measurement of the dipole moments of excited states and photochemical transients by microwave dielectric absorption, J. Phys. Chem., 1982, 86, 3803–3811.

    Article  CAS  Google Scholar 

  21. M. V. Encinas, J. C. Scaiano, Laser photolysis study of the exciplex between triplet benzil and triethylamine, J. Am. Chem. Soc., 1979, 101, 7740–7741.

    Article  CAS  Google Scholar 

  22. W. G. McGimpsey, J. C. Scaiano, A two photon study of the “reluctant” Norrish type I reaction of benzil, J. Am. Chem. Soc., 1987, 109, 2179–2181.

    Article  CAS  Google Scholar 

  23. J. C. Scaiano, Photochemical and free-radical processes in benzil-amine systems. Electron-donor properties of a-aminoalkyl radicals, J. Phys. Chem., 1981, 85, 2851–2855.

    Article  CAS  Google Scholar 

  24. I. Lucak, P. Hrdlvic, Preparation and photochemical properties of 4-propeniyl-benzil polymers, Macromol. Chem. Phys., 1994, 195, 2233–2245.

    Article  Google Scholar 

  25. I. Lucak, C. Kosa, The formation of dibenzoyl peroxide by photooxidation of benzil in a polymer film, Macromol. Rapid Commun., 1994, 15, 929–934.

    Article  Google Scholar 

  26. M. Mukai, S. Yamaushi, N. J. Hirota, Time-resolved EPR study on the photochemical reactions of benzil, J. Phys. Chem., 1992, 96, 3305–3311.

    Article  CAS  Google Scholar 

  27. J. Szejtli, Introduction, general overview of cyclodextrin chemistry, Chem. Rev., 1998, 98, 1743–1753.

    Article  CAS  Google Scholar 

  28. V. Ramamurthy, Organic photochemistry in organized media, Tetrahedron, 1986, 42, 5753–5839.

    Article  CAS  Google Scholar 

  29. W. J. Leigh and L. J. Johnson, in Handbook of Organic Photochemistry, ed. J. C. Scaiano, CRC Press, Boca Raton, 1989, vol. 1, ch. 2, pp. 401–422.

  30. F. Wilkinson, C. J. Wilisher, Triplet-triplet absorption in microcrystalline benzil detected by diffuse reflectance laser flash photolysis, Appl. Spectrosc., 1984, 39, 897–901.

    Article  Google Scholar 

  31. C. Huggenberger, J. Lipscher, H. Fisher, Self-termination of benzoyl radicals to ground- and excited-state benzil. Symmetry control of a radical combination, J. Phys. Chem., 1980, 84, 3467–3474.

    Article  CAS  Google Scholar 

  32. H. Fischer, R. Baer, R. Hany, I. Verhoolen, M. Walbiner, 2,2-Dimetoxy-2-phenylacetophenone: photochemistry and free radical photofragmentation, J. Chem. Soc., Perkin Trans. 2, 1990 787–798.

    Google Scholar 

  33. W. Knolle, U. Muller, R. Mehnert, Radiation-induced reactions of benzoyl chloride and acrylates in solution. A pulse radiolysis study, Phys. Chem. Chem. Phys., 2000, 2, 1425–1430.

    Article  CAS  Google Scholar 

  34. B. M. Monroe, in Advances in Photochemistry, ed. J. N. Pitts, G. S. Hammond and W. A. Noyes. J. Wiley and Sons, New York, 1971, vol. 8, pp. 77–108.

  35. T. Hancock-Chen, J. C. Scaiano, Non-linear effects and a cascade of radical events leading to laser-specific generation of active oxygen species, Photochem. Photobiol., 1998, 67, 174–178.

    Article  CAS  Google Scholar 

  36. S. Monti, N. Camaioni, P. Bortolus, Photochemistry in a cyclodextrin cavity. Primary processes in the photoreduction of 3- and 4-benzopyridine studied by laser flash-photolysis, Photochem. Photobiol., 1991, 54, 577–584.

    Article  CAS  Google Scholar 

  37. M. N. Lehmann, M. G. Bakker, H. Patel, M. L. Partin, S. J. Dormady, The effect of inclusion in ß-cyclodextrin on the chemistry of peroxides: Reactions of radicals with ß-cyclodextrin, J. Inclusion Phenom. Mol. Recognit. Chem., 1995, 23, 99–117.

    Article  CAS  Google Scholar 

  38. N. K. Shrestha, E. J. Yagi, Y. Takatori, A. Kawai, Y. Kajii, K. Shibuya, K. Obi, Photochemical a-cleavage reaction of benzoin and its derivatives, J. Photochem. Photobiol., A, 1998, 116, 179–185.

    Article  CAS  Google Scholar 

  39. F. D. Lewis, R. T. Lanterbach, H. G. Heine, Photochemical a-cleavage of benzoin derivatives. Polar transition states for free radical formation, J. Am. Chem. Soc., 1975, 97, 1519–1525.

    Article  CAS  Google Scholar 

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Vieira Ferreira, L.F., Ferreira Machado, I., Da Silva, J.P. et al. A diffuse reflectance comparative study of benzil inclusion within microcrystalline cellulose and β-cyclodextrin. Photochem Photobiol Sci 3, 174–181 (2004). https://doi.org/10.1039/b307956b

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