FACTORS IN FORMATION OF ISOMERICALLY AND OPTICALLY PURE ALKYL-HALIDES .11. VILSMEIER REAGENTS FOR REPLACEMENT OF A HYDROXY-GROUP BY CHLORINE OR BROMINE
FACTORS IN FORMATION OF ISOMERICALLY AND OPTICALLY PURE ALKYL-HALIDES .11. VILSMEIER REAGENTS FOR REPLACEMENT OF A HYDROXY-GROUP BY CHLORINE OR BROMINE
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DOI：
10.1039/p19760000754
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发表时间：
1976-01-01
期刊：
影响因子：
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通讯作者：
HUDSON, HR
中科院分区：
文献类型：
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作者：
HEPBURN, DR;HUDSON, HR
Vilsmeier试剂[Me_2NCHX]+X-（X = Cl或Br）与醇类反应生成相应的卤代烷。通过使用水溶性溶剂促进产物的分离。除了在支链仲醇例如3-甲基丁-2-醇的情况下，很少或不发生烷基的重排。在二氧六环或乙腈中，（+）-辛-2-醇产生光学纯的氯化物，构型反转，尽管在二甲基甲酰胺中发生一些外消旋化。得到的2-溴辛烷没有可检测到的重排，光学纯度约为100%。75%在二氧六环中反应。
Vilsmeier reagents, [Me2NCHX]+X–(X = Cl or Br), interact with alcohols to give good yields of the corresponding alkyl halides. Isolation of the product is facilitated by the use of water-soluble solvents. Little or no rearrangement of the alkyl group occurs, except in the case of a branched-chain secondary alcohol, e.g. 3-methylbutan-2-ol. In dioxan or acetonitrile, (+)-octan-2-ol yields the optically pure chloride with inversion of configuration, although some racemisation occurs in dimethylformamide. 2-Bromo-octane is obtained with no detectable rearrangement and with an optical purity of ca. 75% by reaction in dioxan.