Influence of methoxy substitution on flavonoid photophysics: A steady state and laser flash photolysis study

被引：20

作者：

Christoff, M ^{[1
]}

Toscano, VG ^{[1
]}

Baader, WJ ^{[1
]}

机构：

[1] UNIV SAO PAULO,INST QUIM,BR-05599970 SAO PAULO,BRAZIL

来源：

JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY | 1996年 / 101卷 / 01期

基金：

巴西圣保罗研究基金会;

关键词：

flavonoid photophysics; laser flash photolysis; methoxy substitution; steady state photolysis;

D O I：

10.1016/S1010-6030(96)04422-X

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

A comparative study of the photophysical properties of three flavonoids (flavone (F), 7-methoxyflavone (7MF) and 3-methoxyflavone (3MF)), which may serve as models for naturally occurring flavonoids, shows a distinct behaviour of the 3-methoxy derivative. Steady state and transient spectroscopic investigations reveal an almost quantitative formation of the triplet states of F and 7MF, which can be observed as transient absorptions and show electron donor and acceptor properties. In contrast, 3MF shows reduced triplet formation, and the transient observed is identified as a I,4-biradical, formed by intramolecular hydrogen abstraction, which behaves as an electron donor.

引用

页码：11 / 20

页数：10

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