THE FORMATION OF FREE RADICALS BY REDUCTION WITH VANADOUS CHLORIDE: Preliminary Paper
THE FORMATION OF FREE RADICALS BY REDUCTION WITH VANADOUS CHLORIDE: Preliminary Paper
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通过氯化钒还原形成自由基：初步论文
DOI：
10.1021/ja01663a032
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发表时间：
1923
影响因子：
15
通讯作者：
A. W. Sloan
中科院分区：
文献类型：
--
作者：
J. Conant;A. W. Sloan
向氯化三苯基吡喃鎓（Ⅰ）的溶液中加入氯化钒，导致形成一种微红色沉淀，它可以在相当纯的条件下通过在二氧化碳气氛中过滤得到。这种有色的不溶性物质表现得像自由基;它的氯仿溶液是鲜红色的，当溶液与空气一起摇动时颜色消失。该物质被氯化铁再氧化为吡喃盐;如果该过程在无氧条件下定量进行，则最多需要一个氯化铁分子。远低于这个量就足以氧化一种沉淀物，即使在二氧化碳气氛中放置几个小时;该化合物显然不稳定。虽然这些事实清楚地表明我们正在研究一种自由基，但我们仍希望获得更积极的证据。因此，我们研究了在苯溶液中，通过金属的作用，从Gomberg 1得到自由基苯基黄嘌呤基的氯化物中还原苯基黄嘌呤酚（II）的盐。苯基黄原酚在锥形盐酸中轻微溶解，产生橙色溶液。这种溶液可能含有氯化物，其氧鎓式（III）可以写成。这种盐比吡喃盐更容易水解，因此必须用锥形的盐酸溶液进行处理。当这种氯化苯基黄嘌呤溶液用氯化钒处理时，
The addition of vanadous chloride to a solution of triphenylpyrylium chloride (I) causes the formation of a reddish precipitate which can be obtained in a fairly pure condition by filtering in an atmosphere of carbon dioxide. This colored, insoluble substance behaves like a free radical; a chloroform solution of it is bright red and the color disappears when the solution is shaken with air. The substance is reoxidized to the pyrylium salt by ferric chloride; if this process is carried out quantitatively in the absence of oxygen a maximum of one molecule of ferric chloride is required. Considerably less than this amount suffices to oxidize a precipitate which has stood for some hours even in an atmosphere of carbon dioxide; the compound is apparently unstable. While these factsclearly indicated that we were dealing with a free radical, we desired to obtain still more positive evidence. We, therefore, investigated the reduction of the salts of phenylxanthenol (II) from the chloride of which Gomberg1 obtainedthe free radical phenylxanthyl by the action of metals in benzene solution. Phenylxanthenol dissolves to a slight extent in coned, hydrochloric acid, producing an orange-colored solution. This solution presumably contains a chloride for which the oxonium formula (III) can be written. This salt is much more readily hydrolyzed than the pyrylium salt, so that it is necessary to work with coned, hydrochloric acid solutions. When such a solution of phenyl-xanthylium chloride is treated with vanadous chloride a brown precipitate