Manifestation of the dynamics of ultrafast photoprocesses in the transient absorption spectra of diflavonoid solutions
https://doi.org/10.29235/1561-2430-2021-57-2-224-231
Abstract
Herein, using the femtosecond absorption spectroscopy method, the dynamics of the nonstationary induced absorption spectra of diflavonoid 3,7-dihydroxy-2,8-di(4-methoxyphenyl)-4H, 6H-pyrano[3,2-g]chromene-4,6-dione (DFV) in solvents of different polarities is studied. It is found that the rapid transformation of the transient absorption spectra of DFV in time is due to the processes of intramolecular protons transfer in excited singlet states. For a nonpolar solvent, two protons are transferred in two stages. Initially, during the sub-picosecond times, a form with a single transferred proton is formed from the Frank-Condon state. From this transition state, in a time range of about 9 ps, the second proton is transferred and the two proton transfer tautomer with a high quantum yield of fluorescence ~0.66 is formed, which has the gain band in the transient absorption spectra. For the polar solvent dimethylformamide only the short-lived form with a single proton transferred is formed also during the subpicosecond times practically the same ones as for the nonpolar solution and has a lifetime of about 20 ps. The polarity of the medium, which affects the formation of a set of the “closed” and “open” forms of DFV in the ground state, differing in relative positions in the space of hydroxyl and carbonyl groups, largely determines the mechanism of the intramolecular proton transfer process in the DFV molecule, which consists in the sequential transfer of two protons in a non-polar solvent to form a fluorescent long-lived tautomer and the transfer of one proton in polar solvents to form a short-lived non-fluorescent form.
About the Author
S. A. Tikhomirov
B. I. Stepanov Institute of Physics of the National Academy of Sciences of Belarus
Belarus
Belarus
Sergei A. Tikhomirov – Corresponding Member of the National Academy of Sciences of Belarus, Dr. Sc. (Physics and Mathematics), Chief Researcher of the Center of Photonics of Atoms and Molecules Structures
68-2, Nezavisimosti Ave., 220072, Minsk, Republic of Belarus
References
1. Uzhinov B. M., Khimich M. N. Conformational effects in excited state intramolecular proton transfer of organic compounds. Russian Chemical Reviews, 2011, vol. 80, no. 6, pp. 553–578. https://doi.org/10.1070/rc2011v080n06abeh004144
2. Fang C, Frontiera R. R, Tran R, Mathies R. A. Mapping GFP structure evolution during proton transfer with femtosecond Raman spectroscopy. Nature, 2009, vol. 462, no. 7270, pp. 200–205. https://doi.org/10.1038/nature08527
3. Chou P., McMorrow D., Aartsma T. J., Kasha M. The Proton-Transfer Laser. Gain Spectrum and Amplification of Spontaneous Emission of 3-Hydroxyflavone. Journal of Physical Chemistry, 1984, vol. 88, no. 20, pp. 4596–4599. https://doi.org/10.1021/j150664a032
4. Mishra H., Misra V., Mehata M. S., Pant T. C. Tripathi H. B. Fluorescence Studies of Salicylic Acid Doped Poly (Vinyl Alcohol) Film as a Water/Humidity Sensor. Journal of Physical Chemistry A, 2004, vol. 108, no. 12, pp. 2346–2352. https://doi.org/10.1021/jp0309365
5. Sobolewski A. L. Reversible Molecular Switch Driven by Excited-State Hydrogen Transfer. Physical Chemistry Chemical Physics, 2008, vol. 10, no. 9, pp. 1243–1247. https://doi.org/10.1039/b716075e
6. Zhang Z., Chen Y.-A., Hung W.-Y., Tang W.-F., Hsu Y.-H., Chen C.-L., Meng F.-Y. Chou P.-T. Control of the Reversibility of Excited-State Intramolecular Proton Transfer (ESIPT) Reaction: Host-Polarity Tuning White Organic Light Emitting Diode on a New Thiazolo[5,4- d]Thiazole ESIPT System. Chemistry of Materials, 2016, vol. 28, no. 23, pp. 8815–8824. https://doi.org/10.1021/acs.chemmater.6b04707
7. Yang D., Liu W., Kong L., Zhang Q., Liu Y. Ultrafast excited state intramolecular proton transfer (ESIPT) mechanism for 2,6-bis(benzothiazolyl-2-yl)phenol: A theoretical investigation. Chemical Physics Letters, 2020, vol. 744, pp. 137226. https://doi.org/10.1016/j.cplett.2020.137226
8. Liu Z.-Y., Hu J.-W., Huang T.-H., Chen K.-Y., Chou P.-T. Excited-State Intramolecular Proton Transfer in the Kinetic-Control Regime. Physical Chemistry Chemical Physics, 2020, vol. 22, no. 39, pp. 22271–22278. https://doi.org/10.1039/d0cp03408h
9. Taylor C. A., El-Bayoumi M. A., Kasha M. Excited-State Two-Proton Tautomerism in Hydrogen-Bonded N-Heterocyclic Base Pairs. Proceedings of the National Academy of Sciences, 1969, vol. 63, no. 2, pp. 253–260.https://doi.org/10.1073/pnas.63.2.253
10. Takeuchi S., Tahara T. The answer to concerted versus step-wise controversy for the double proton transfer mechanism of 7-azaindole dimer in solution. Proceedings of the National Academy of Sciences, 2007, vol. 104, no. 13, pp. 5285–5290. https://doi.org/10.1073/pnas.0610141104
11. Kwon O.-H., Zewail A. H. Double Proton Transfer Dynamics of Model DNA Base Pairs in the Condensed Phase. Proceedings of the National Academy of Sciences, 2007, vol. 104, no. 21, pp. 8703–8708. https://doi.org/10.1073/pnas.0702944104
12. Pivovarenko V. G., Jozwiak L., Blazejowski J. 2,8-Bis[4-(diethylamino)phenyl]-3,7-dihydroxy-4H,6H-pyrano[3,2-g] chromene-4,6-dione? A New Liquid-Phase-Sensitive Fluorescent Probe Utilising Intramolecular One- or Two-Proton Transfer Phenomena. European Journal of Organic Chemistry, 2002, vol. 2020, no. 23, pp. 3979–3985. https://doi.org/10.1002/1099-0690(200212)2002:23<3979::aid-ejoc3979>3.0.co;2-5
13. Falkovskaia E., Pivovarenko V. G., del Valle J. C. Interplay between Intra- and Intermolecular Excited-State Singleand Double-Proton-Transfer Processes in the Biaxially Symmetric Molecule 3,7-Dihydroxy-4H,6H-pyrano[3,2-g]-chromene-4,6-dione. The Journal of Physical Chemistry A, 2003, vol. 107, no. 18, pp. 3316–3325. https://doi.org/10.1021/jp021791p
14. Bondarev S. L., Knyukshto V. N., Tikhomirov S. A., Buganov O. V., Pyrko A. N. Photodynamics of intramolecular proton transfer in polar and nonpolar biflavonoid solutions. Optics and Spectroscopy, 2012, vol. 113, no. 4, pp. 401–410. https://doi.org/10.1134/s0030400x12070065
15. Stsiapura V. I., Kurhuzenkau S. A., Kuzmitsky V. A., Bouganov O. V., Tikhomirov S. A. Solvent polarity effect on nonradiative decay rate of Thioflavin T. The Journal of Physical Chemistry A, 2016, vol. 120, no. 28, pp. 5481–5496. https://doi.org/10.1021/acs.jpca.6b02577
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