Electron-rich and electron-poor alkenes have been dibrominated using a rapid and sustainable procedure. The reactions were conducted in aqueous medium and basic ionic liquids which catalyzed the direct addition of bromine. The protocol leads to remarkable results, high yields under mild conditions, complete chemo- and stereo-selectivity and allows the recycling of ionic liquids, reducing costs, and
Stereoselective debromination of aryl-substituted vic-dibromide with indium metal
作者:Brindaban C. Ranu、Sankar K. Guchhait、Arunkanti Sarkar
DOI:10.1039/a806530f
日期:——
Debromination of both meso and dl (erythro and threo) aryl-substituted vic-dibromides with indium metal in MeOH leads to trans-alkenes exclusively.
在甲醇中,钌金属对间位和对位(赤型和苏型)芳基取代的连二溴化物进行脱溴反应,仅生成反式烯烃。
Dibrominated addition and substitution of alkenes catalyzed by Mn<sub>2</sub>(CO)<sub>10</sub>
作者:Xianheng Song、Shanshui Meng、Hong Zhang、Yi Jiang、Albert S. C. Chan、Yong Zou
DOI:10.1039/d1cc04534b
日期:——
A practical method for the dibromination of alkenes without using molecular bromine is consistently appealing in organic synthesis. Herein, we report Mn-catalyzed dibrominated addition and substitution of alkenes only with N-bromosuccinimide, producing a variety of synthetically valuable dibrominated compounds in moderate to high yields.
Solvent-free bromination reactions with sodium bromide and oxone promoted by mechanical milling
作者:Guan-Wu Wang、Jie Gao
DOI:10.1039/c2gc16606b
日期:——
New solvent-free brominations of 1,3-dicarbonyl compounds, phenols, various alkenes including chalcones, azachalcones, 4-phenylbut-3-en-2-one, methyl cinnamate, styrene and 1,3-cyclohexadiene were efficiently achieved by employing sodium bromide and oxone under mechanical milling conditions. The brominated products were obtained in good to excellent yields.
Regio- and stereoselective hydroxybromination and dibromination of olefins using ammonium bromide and oxone®
作者:Arun Kumar Macharla、Rohitha Chozhiyath Nappunni、Narender Nama
DOI:10.1016/j.tetlet.2012.01.026
日期:2012.3
synthesis of vicinal bromohydrins and dibromides fromolefins is presented. Various olefins are regio- and stereoselectively hydroxybrominated and dibrominated with anti fashion, following Markonikov’s rule, using eco-friendly, non-toxic, and stable reagents such as NH4Br and oxone® in CH3CN/H2O (1:1) and CH3CN without employing catalyst in moderate to excellent yields. Bromohydrins are formed instantaneously