化学
甲醇钠
甲醇
水溶液
甲醇
一氧化碳
氧化裂解
基础(拓扑)
药物化学
劈理(地质)
立体化学
催化作用
有机化学
数学分析
数学
岩土工程
断裂(地质)
工程类
作者
Akira Nishinaga,Tetsuo Tojo,Hiroya Tomita,Teruo Matsuura
出处
期刊:Journal of the Chemical Society
日期:1979-01-01
卷期号:: 2511-2511
被引量:51
摘要
3-Hydroxyflavones, except those containing a 7-hydroxy-group, undergo base-catalysed oxygenolysis under mild conditions leading to oxidative cleavage of the heterocyclic ring to give the corresponding depsides and carbon monoxide in excellent yields. The same result is obtained in the reaction of quercetinase, a dioxygenase. The oxygenation of 3,4′,7-trihydroxyflavone in aqueous solution gave p-hydroxyphenylglyoxylic acid and 2,4-dihydroxybenzoic acid; in absolute methanol containing sodium methoxide methyl 4-hydroxyphenylglyoxylate and methyl 2,4-dihydroxybenzoate as well as 4-hydroxyphenylglyoxylic acid were obtained. The formation of these products is rationalized by assuming that 2-hydroperoxy-4′,7-dihydroxyflavan-3,4-dione is formed first and is reduced with the intervention of the 7-hydroxy-group to give 2,4′,7-trihydroxyflavan-3,4-dione, which is solvated and oxidized under the reaction conditions. 2′-Substituted-3-hydroxyflavones were not susceptible to oxygenolysis.
科研通智能强力驱动
Strongly Powered by AbleSci AI