Investigation of the Preparation of Bromides from 1-, 2- and 3-Pentanol. Synthesis of Pure Bromopentanes
Investigation of the Preparation of Bromides from 1-, 2- and 3-Pentanol. Synthesis of Pure Bromopentanes
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由 1-、2- 和 3-戊醇制备溴化物的研究。
DOI：
10.1021/ja01136a027
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发表时间：
1952
影响因子：
15
通讯作者：
V. Ipatieff
中科院分区：
文献类型：
--
作者：
H. Pines;A. Rudin;V. Ipatieff
本文研究了溴对1-、2-和3-戊醇中羟基的取代反应，着重研究了反应过程中的异构化反应。用红外光谱分析法测定了异构化程度。用溴化钠与相应醇的甲苯磺酸酯作用，制备了红外标准用的纯1-、2-和3-溴戊烷。3-溴代戊烷与溴化氢或硫酸作用时会异构化为2-溴代戊烷。从相应的醇制备溴化物的常用方法包括使用气态溴化氢、2三溴化磷或3溴化氢水溶液与硫酸。[4]用文献中所述的方法将仲醇转化为溴化物可能是通过碳正离子进行的，因此，该反应可能伴随着重排。这种重排的可能性是由涉及苯烷基化过程中的异构化的研究表明的。
The replacement of the hydroxy group in 1-, 2-and 3-pentanolby bromine was studied with special emphasis on the isom-erization occurring during the reaction. Infrared spectral analysis was applied to determine the degree ofisomerization. Pure 1-, 2-and 3-bromopentane for infrared standards were prepared by the action of sodium bromide on the tosylate esters of the corresponding alcohols. 3-Bromopentane undergoes isomerization to 2-bromopentane when treated with hydrogen bromide or with sulfuric acid.The usual methods for the preparation of bro-mides from the corresponding alcohols involve the use of gaseous hydrogen bromide, 2 phosphorus tri-bromide, 3 or aqueous hydrogenbromide with sul-furic acid. 4 The conversion of a secondary alcohol to the bromide by the methods indicated in the literature is likely to proceed via a carbonium ion, and for that reason this reaction might be accom-panied by rearrangement. The possibility of such a rearrangement was indicated by studies which involved isomerization during the alkylation of ben-