REDUCTION OF ALPHA-HALO KETONES BY ORGANOTIN HYDRIDES - AN ELECTRON-TRANSFER-HYDROGEN ATOM ABSTRACTION MECHANISM
REDUCTION OF ALPHA-HALO KETONES BY ORGANOTIN HYDRIDES - AN ELECTRON-TRANSFER-HYDROGEN ATOM ABSTRACTION MECHANISM
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DOI：
10.1021/jo00376a024
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发表时间：
1986-12-26
影响因子：
3.6
通讯作者：
SINGH, HK
中科院分区：
文献类型：
--
作者：
TANNER, DD;SINGH, HK
研究了三苯基锡氢化物还原氯代和溴代苯乙酮的反应机理。减少被发现遵循相同的减少途径，如先前已报道的减少-氟苯乙酮。均裂反应和异裂反应都可以被识别，因为均裂反应产生苯乙酮，异裂反应产生α-（卤甲基）苄醇。均裂还原通过自由基链式过程进行，其中引发步骤和传播步骤之一涉及SET反应。还原过程中没有观察到二次氘同位素效应，因此还原过程显然不是通过直接的卤素转移进行的。
The mechanism for the reduction of-chloro-and-bromoacetophenone with triphenyltin hydride was investigated. The reductions were found to follow the same reduction pathways as has previously been reported for the reduction of-fluoroacetophenone. Both homolytic and heterolytic reactions could be recognized since the homolytic reactions yield acetophenone and the heterolytic reactions yield a-(halomethyl) benzyl alcohol. The homolytic reductions proceed by a free-radical chain process where the initiation step and one of the propagation steps involve SET reactions. The reduction apparently does not proceedby a direct halogen transfer since no secondary deuterium isotope effect was observed on reduction of a, a-dideuterio-a-haloacetophenone.