Electron magnetic resonance of phenoxy radicals
Electron magnetic resonance of phenoxy radicals
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苯氧基自由基的电子磁共振
DOI：
10.1039/tf9605600459
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发表时间：
1960
期刊：
影响因子：
--
通讯作者：
G. Scott
中科院分区：
文献类型：
--
作者：
J. Becconsall;S. Clough;G. Scott
除了一个或两个例外，只有那些至少有一个庞大的邻位基团的酚类才能产生可检测到的自由基。从具有两个庞大邻位基团的那些化合物获得最强的信号。光谱都显示超精细结构，在许多情况下，这可以解释在一个单一的自由基物种涉及一个或多个相互作用常数。当存在一种以上的自由基物质时，相对浓度通常随时间变化，或者可以通过改变所使用的氧化剂的量来影响，从而使光谱能够被解释。在表1中给出了化合物的结果，其初始光谱用伯苯氧基基团识别。在许多情况下，一段时间后，初级自由基被相对更稳定的次级自由基所取代，其性质将在后面讨论。对于某些化合物，未观察到伯苯氧基自由基，测得的第一个光谱对应于仲自由基的形成。表2收集了这类结果。
RESULTSWith one or two exceptions, only those phenols which have at least one bulky ortho group gave detectable amounts of free radicals. The most intense signals were obtained from those compounds having two bulky ortho groups. The spectra all showed hyperfine structure, and in many cases this could be explained in terms of a single radical species involving one or more interaction constants. When more than one radical species was present, the relative concentration usually changed with time, or could be influenced by varying the amount of oxidizing agent used, so enabling the spectrum to be interpreted. In table 1 are presented results from compounds for which the initial spectrum is identified with the primary phenoxy radical. In many cases the primary radical is replaced after some time by a secondary radical of relatively greater stability, the identity of which is discussed later. For some compounds the primary phenoxy radical has not been observed, the first spectrum measured corresponding to the formation of the secondary radical. Results of this type are collected in table 2.