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
Facile and Efficient Method for the Debromination of<i>vic</i>-Dibromides to Alkenes with BiCl<sub>3</sub>/Ga System
作者:Byung Woo Yoo、Seo Hee Kim、Young Kwang Park
DOI:10.1080/00397911.2010.542568
日期:2012.6
Abstract BiCl3/Ga was found to be a mild, efficient, and chemoselective system for the debromination of a series of functionally and structurally various vic-dibromides. A broad range of functional groups (ester, carboxy, aldehyde, methoxy, chloro, and ketone) was tolerated under the reaction conditions and only trans olefins were obtained in good yields. GRAPHICAL ABSTRACT
Visible-Light Photoredox Catalysis: Dehalogenation of Vicinal Dibromo-, α-Halo-, and α,α-Dibromocarbonyl Compounds
作者:Tapan Maji、Ananta Karmakar、Oliver Reiser
DOI:10.1021/jo102239x
日期:2011.1.21
vic-Dibromo-, α-halo-, or α,α-dibromocarbonylcompounds can be efficiently dehalogenated using catalytic tris(2,2′-bipyridyl)ruthenium dichloride (Ru(bpy)3Cl2) in combination with 1,5-dimethoxynaphthalene (DMN) and ascorbate as sacrificial electron donor. For this process, a visible light promoted photocatalytic cycle is proposed that involves the reduction of carbon halogen bonds via free radical
Selenium-catalysed debromination of vic-dibromides to alkenes with cysteine or glutathione
作者:Kazuo Yanada、Reiko Yanada、Haruo Meguri
DOI:10.1039/c39900000730
日期:——
Sodium selenite catalyses, under mild conditions, the reductive debromination of vic-dibromides [e.g., meso- or (±)-1,2-dibromo-1,2-diphenylethane, trans-10,11-dibromodibenzosuberone, 2,3-dibromo-1,3-Biphenyl-1-propanone, α,β-dibromobenzenepropanoic acid, and cholesterol dibromide] to alkenes in the presence of the thiols cysteine or glutathione.
Rapid and Efficient Debromination of vic-Dibromides with VCl<sub>3</sub>/Indium System
作者:Woo Yoo, Byung、Yeon Park, Jee、Jong Shin, Hyo
DOI:10.5012/jkcs.2018.62.4.275
日期:——
The $VCl_3$/In system was found to be a new protocol for debromination of a variety of vic-dibromides to the corresponding alkenes in high yields with short reaction times under mild conditions. This new methodology is highly chemoselective, tolerating several functional groups such as chloro, bromo, fluoro, keto, ester, carboxyl, and methoxy groups.