New aspects of the telluroxide elimination: a facile elimination of sec-alkyl phenyl telluroxide leading to olefins, allylic alcohols, and allylic ethers
New aspects of the telluroxide elimination: a facile elimination of sec-alkyl phenyl telluroxide leading to olefins, allylic alcohols, and allylic ethers
复制标题
碲氧化物消除的新方面：轻松消除仲烷基苯基碲氧化物，生成烯烃、烯丙醇和烯丙醚
DOI：
10.1021/ja00347a039
复制
发表时间：
1983
期刊：
影响因子：
--
通讯作者：
S. Fukuzawa
中科院分区：
文献类型：
--
作者：
S. Uemura;S. Fukuzawa
碲氧化物用于烯烃合成的效用，以前似乎是没有什么价值的反应进行了描述。在室温下用NaOH水溶液处理仲烷基苯基碲二溴化物（环己基体系除外），可以得到烯烃、烯丙醇和/或烯丙基醚，产率很高，推测是通过形成仲烷基苯基碲氧化物和它们的碲氧化物消除。对于直链烯烃的形成，观察到比硒氧化物和亚砜消除更倾向于消除朝向较少取代的碳。在环十二烷基的情况下，只有反式-环十二碳烯作为烯烃组分在一个尖锐的反式中形成，以提供顺式和反式异构体的1：1混合物的硒氧化物消除。相反，在正烷基和环己基的情况下，相应的碲氧化物是稳定的化合物，其仅通过在高于200 ℃的温度下的纯热解提供包括乙烯基醚的类似消除产物。
The utility of the telluroxide for olefin synthesis, a reaction which previously appeared to be of little value is described. Treatment of sec-alkylphenyltellurium dibromides, except for the cyclohexyl system, with aqueous NaOH at room temperature affords olefins, allylic alcohols, and/or allylic ethers in high yields presumably via the formation of sec-alkyl phenyl telluroxides and their facile telluroxide elimination. As to the formation of linear olefins, more preference for elimination toward the less substituted carbon was observed than the selenoxide and sulfoxide eliminations. In the cyclododecyl case only trans-cyclododecene was formed as an olefin componenet in a sharp constrast to the selenoxide elimination that affords a 1:1 mixture of cis and trans isomers. On the contrary, in the n-alkyl and cyclohexyl cases the corresponding telluroxides are stable compounds that afford similar elimination products including vinylic ethers only by neat pyrolysis at temperatures above 200/sup 0/C.