SPECTRAL AND BASIC PROPERTIES OF FLAVONES IN THE GROUND AND EXCITED STATES: UDC 547.814.5 + 54.04

A. Varenikov; I. Serdiuk; A. Roshal

Автор(и)

A. Varenikov, mgr Харківський національний університет імені В. Н. Каразіна
I. Serdiuk, PhD student Харківський національний університет імені В. Н. Каразіна , University of Gdańsk
A. Roshal, Dr. hab. Харківський національний університет імені В. Н. Каразіна

Ключові слова:

flavones, electronic spectroscopy, acid-base properties, protolytic equilibria

Анотація

Dependence between structures of R-oxyflavones and their spectral and basic properties has been investigated. It was found that pK_a of flavones, depending on positions of hydroxy and methoxy groups, increase by 6-8 orders of magnitude upon excitation and reaches 3.7-6.6 units. Due to high pK_a* value carbonyl group can serve as a proton acceptor in the excited-state intramolecular proton transfer as well as in the formation of phototautomers of 7- and 4'-hydroxyflavones in protic solvents.

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