28467-71-2Relevant articles and documents
A simple and effective co-catalyst for ring-closing enyne metathesis using Grubbs I type catalysts: A practical alternative to "Mori's conditions"
Lloyd-Jones, Guy C.,Robinson, Alan J.,Lefort, Laurent,De Vries, Johannes G.
, p. 9449 - 9452 (2010)
"Catch-and-release": Simple alk-1-enes are effective at liberating buta-1,3-dienes from vinyl alkylidene ruthenium complexes, as well as undergoing alkene-alkylidene exchange with enyne substrates to regenerate the alk-1-ene. This ability to "catch-andrelease" ruthenium alkylidenes allows alk-1-enes higher than ethylene ("Mori's conditions") to be used as a co-catalysts in terminal enyne metathesis with the Grubbs generation I complex (L=PCy3).
Laser flash photolysis determination of absolute rate constants for reactions of bromine atoms in solution
Scaiano,Barra,Krzywinski,Sinta,Calabrese
, p. 8340 - 8344 (1993)
The photodecomposition of vicinal dibromides at 266 nm produces bromine atoms with a quantum yield of ～2.0. This results from an efficient primary photocleavage of a C-Br bond, followed by rapid elimination of a second bromine atom from radicals of the ty
Linear Paired Electrolysis—Realising 200 % Current Efficiency for Stoichiometric Transformations—The Electrochemical Bromination of Alkenes
Strehl, Julia,Abraham, Marvin L.,Hilt, Gerhard
supporting information, p. 9996 - 10000 (2021/03/31)
The generation of bromine by oxidation of bromide anions at the anode and reduction of molecular oxygen at the cathode to hydrogen peroxide resulted in the overall formation of two molecules of Br2 (=four electron oxidation) by passing just two electrons through the solution. The bromine was used for the bromination of alkenes and thereby a linear paired electrolysis was attained which resulted in current efficencies of up to 200 %. Also, the diiodination of cyclohexene as well as the electrophilic aromatic bromination of an electron-rich arene were realised both in 168 % current efficiencies.
A Highly Efficient Method for the Bromination of Alkenes, Alkynes and Ketones Using Dimethyl Sulfoxide and Oxalyl Bromide
Ding, Rui,Li, Jiaqi,Jiao, Wenyi,Han, Mengru,Liu, Yongguo,Tian, Hongyu,Sun, Baoguo
, p. 4325 - 4335 (2018/11/21)
The pairing of DMSO and oxalyl bromide is reported as a highly efficient brominating reagent for various alkenes, alkynes and ketones. This bromination approach demonstrates remarkable advantages, such as mild conditions, low cost, short reaction times, provides excellent yields in most cases and represents a very attractive alternative for the preparation of dibromides and α-bromoketones.
Method for preparing o-dibromo compounds from olefins
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Paragraph 0010; 0011, (2018/09/28)
The invention relates to a method for preparing o-dibromo compounds from olefins, and the structural formulae of the o-dibromo compounds are as follows. The method comprises the following steps: dropwise adding a dichloromethane solution of dimethyl sulfoxide (1.5 equiv) into a dichloromethane solution of oxalyl bromide (1.5 equv) at a temperature of -10 DEG C, then dropwise adding a raw materialolefin, and then recovering the temperature to room temperature or carrying out heating to 30-40 DEG C, carrying out a reaction to obtain the corresponding o-dibromo compounds, wherein the yield is ina range of 79-97%.
Mild and Efficient Vicinal Dibromination of Olefins Mediated by Aqueous Ammonium Fluoride
Ng, Wing Hin,Shing, Tony K. M.,Yeung, Ying-Yeung
supporting information, p. 419 - 424 (2018/02/23)
A mild and efficient vicinal dibromination of olefins has been developed by using saturated aqueous ammonium fluoride solution as the promoter. Inexpensive and commercially available N -bromosuccinimide (NBS) was used as the brominating reagent. The corresponding vicinal dibromoalkanes could be obtained in good to excellent yields.
Oxidative bromination reactions in aqueous media by using Bu4NBr/TFA/H2O2 system
Moriuchi, Toshiyuki,Fukui, Yasuhiro,Sakuramoto, Takashi,Hirao, Toshikazu
supporting information, p. 1708 - 1710 (2017/11/23)
Metal-free oxidative bromination reactions in aqueous media were performed using tetrabutylammonium bromide, trifluoroacetic acid, and hydrogen peroxide under mild conditions. Oxidative bromination reaction of alkenes was found to afford the corresponding vic-bromides. Furthermore, this oxidative bromination system is applicable to the oxidative bromination of alkynes, arenes, and 3,4-dihydronaphthalen-1(2H)-one. A gram-scale bromination reaction was also performed successfully.
Efficient bromination of olefins, alkynes, and ketones with dimethyl sulfoxide and hydrobromic acid
Song, Song,Li, Xinwei,Sun, Xiang,Yuan, Yizhi,Jiao, Ning
supporting information, p. 3285 - 3289 (2015/06/25)
The oxidative bromination of olefins, alkynes, and ketones has been developed with HBr as the brominating reagent and DMSO as the mild oxidant. The simple conditions, high bromide-atom-economy, as well as easy accessibility and low cost of DMSO and HBr make the present strategy prospective for the synthesis of dibrominated alkanes, dibrominated alkenes and α-bromoketones.
Brominations with Pr4NBr9 as a solid reagent with high reactivity and selectivity
Beck, Thorsten M.,Haller, Heike,Streuff, Jan,Riedel, Sebastian
, p. 740 - 747 (2014/04/03)
Tetrapropylammonium nonabromide (Pr4NBr9) is introduced as a room-temperature solid reagent for rapid bromination reactions of various substrates. The reagent exhibits reactivity similar to that of elemental bromine, but shows higher selectivity and it is easier and safer to store and to handle. Georg Thieme Verlag Stuttgart · New York.
Brominated methanes as photoresponsive molecular storage of elemental Br2
Kawakami, Kazumitsu,Tsuda, Akihiko
, p. 2240 - 2252 (2012/11/06)
The photochemical generation of elemental Br2 from brominated methanes is reported. Br2 was generated by the vaporization of carbon oxides and HBr through oxidative photodecomposition of brominated methanes under a 20 W low-pressure mercury lamp, wherein the amount and situations of Br2 generation were photochemically controllable. Liquid CH 2Br2 can be used not only as an organic solvent but also for the photoresponsive molecular storage of Br2, which is of great technical benefit in a variety of organic syntheses and in materials science. By taking advantage of the in situ generation of Br2 from the organic solvent itself, many organobromine compounds were synthesized in high practical yields with or without the addition of a catalyst. Herein, Br2 that was generated by the photodecomposition of CH2Br2 retained its reactivity in solution to undergo essentially the same reactions as those that were carried out with solutions of Br2 dissolved in CH 2Br2 that were prepared without photoirradiation. Furthermore, HBr, which was generated during the course of the photodecomposition of CH2Br2, was also available for the substitution of the OH group for the Br group and for the preparation of the HBr salts of amines. Furthermore, the photochemical generation of Br2 from CH2Br2 was available for the area-selective photochemical bleaching of natural colored plants, such as red rose petals, wherein Br2 that was generated photochemically from CH 2Br2 was painted onto the petal to cause radical oxidations of the chromophoric anthocyanin molecules. The generation of Br 2 from brominated methanes occurred upon photoirradiation under O2. The solutions that contained elemental Br2 were useful for the synthesis of organobromine compounds and the macroscopic photochemical bleaching of colored plants. Copyright
