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
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
I2O5-mediated bromohydroxylation and dibromination of olefins using KBr in water
作者:Yajun Wang、Jinxi Wang、Yun Xiong、Zhong-Quan Liu
DOI:10.1016/j.tetlet.2014.03.064
日期:2014.4
An efficient and green bromohydroxylation and dibromination of various olefins mediated by I2O5 has been developed in this work. A series of olefins gave the corresponding α-bromo-alcohols and dibromides as the major products using KBr as the brominating reagent in aqueous medium at room temperature. The diastereo- and regio-selectivities are extremely high.
在这项工作中,已经开发了由I 2 O 5介导的各种烯烃的有效且绿色的溴羟基化和二溴化。在室温下,在水介质中使用KBr作为溴化试剂,一系列烯烃得到了相应的α-溴代醇和二溴化物作为主要产物。非对映选择性和区域选择性非常高。