Superphotoacidic properties and pH-switched Stokes shifts in electron-deficient 5-hydroxyisoquinolone derivatives

Superphotoacidic properties and pH-switched Stokes shifts in electron-deficient 5-hydroxyisoquinolone derivatives Full article

Journal

Journal of Photochemistry and Photobiology A: Chemistry
ISSN: 1010-6030 , E-ISSN: 1873-2666

Output data

Year: 2022, Volume: 427, Article number : 113808, Pages count : DOI: 10.1016/j.jphotochem.2022.113808

Authors

Salikov Rinat F. ^1,2 , Belyy Alexander Yu. ² , Trainov Konstantin P. ² , Velmiskina Julia A. ^3,2,4 , Medvedev Michael G. ^3,2 , Korshunov Vladislav M. ⁵ , Taydakov Ilya V. ⁵ , Platonov Dmitry N. ² , Tomilov Yury V. ²

Affiliations

1	Higher School of Economics National Research University, Russian Federation
2	N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp, 119991 Moscow, Russian Federation
3	D. Mendeleev University of Chemical Technology of Russia, Higher Chemical College of the Russian Academy of Sciences, Zelinsky Street 38-8, 80, 11733 Moscow, Russian Federation
4	X-ray Structural Laboratory, A.N. Nesmeyanov Institute of Organoelement Compounds RAS, Vavilov St. 28, Moscow, Russian Federation
5	P. N. Lebedev Physical Institute of the Russian Academy of Sciences, 53 Leninsky Prospect, 119991 Moscow, Russia

Four electron-deficient 5-hydroxyisoquinolones are among the strongest currently known superphotoacids with excited state pKa* down to −5.8 and ΔpKa up to 9.0, as estimated experimentally via Förster cycle and supported by quantum chemical calculations. A condensed teracyclic derivative is a weaker photoacid with ΔpKa of around three units. The superphotoacidity in turn initiates pH-switched Stokes shifts: irrespective of the form (protonated or deprotonated) absorbing the photon, only emission of the deprotonated form is observed in protic media.

Salikov R.F. , Belyy A.Y. , Trainov K.P. , Velmiskina J.A. , Medvedev M.G. , Korshunov V.M. , Taydakov I.V. , Platonov D.N. , Tomilov Y.V.
Superphotoacidic properties and pH-switched Stokes shifts in electron-deficient 5-hydroxyisoquinolone derivatives
Journal of Photochemistry and Photobiology A: Chemistry. 2022. V.427. 113808 . DOI: 10.1016/j.jphotochem.2022.113808 WOS Scopus OpenAlex

≡ Web of science:	WOS:000783041100003
≡ Scopus:	2-s2.0-85123890772
≡ OpenAlex:	W4206827519