在这项工作中,我们发现H 2 O 2 –HBr(aq)系统可以从脂肪族和仲苄醇合成α-一溴酮和α,α'-二溴酮,收率高达91%。通过改变过氧化氢和氢溴酸的量,可以选择性地引导该过程形成单溴酮或二溴酮。应用方便、设备简单、反应活性多方面以及符合绿色化学原理,使得H 2 O 2 –HBr(aq)系统的应用在实验室和工业界非常有吸引力。尽管已知酮具有通过Baeyer-Villiger反应氧化或在过氧化氢和布朗斯台德酸存在下形成具有O-O部分的化合物过氧化的已知特性,但所提出的氧化-溴化过程是选择性的。
Highly diastereoselective synthesis of substituted epichlorohydrins and regioselective preparation of allyl alcohols using chloro or iodomethyllithium
作者:JoséM. Concellón、Luján Llavona、Pablo L. Bernad
DOI:10.1016/0040-4020(95)90943-q
日期:1995.5
Substituted epichlorohydrins 3 or 6 are obtained from α-bromo or α-chlorocarbonyl compounds (1 or 4) and chloro or iodomethyllithium, respectively. Starting from α-bromocarbonyl compounds 1 or acyclic α-chloro ketones the reaction takes place with total diastereoselectivity. Treatment of epichlorohydrins 3 or 6 with lithium iodide affords the same substituted allyl alcohols 7 in a regioselective manner