31778-29-7Relevant academic research and scientific papers
Alkene, Bromide, and ROH – How To Achieve Selectivity? Electrochemical Synthesis of Bromohydrins and Their Ethers
Bityukov, Oleg V.,Nikishin, Gennady I.,Terent'ev, Alexander O.,Vil', Vera A.
supporting information, p. 3070 - 3078 (2021/05/10)
Bromohydrins and their ethers were electrochemically synthesized via hydroxy- and alkoxybromination of alkenes using potassium bromide and water or alcohols. High selectivity of bromohydrins formation was achieved only with the use of DMSO as the solvent and an acid as the additive. The proposed combination of starting reagents, additives, and solvents allowed to form bromohydrins or their ethers selectively despite the variety of side-products (epoxides, dibromides, diols). Bromohydrins were obtained in high yields, up to 96%, with a broad substrate scope in an undivided electrochemical cell equipped with glassy carbon and platinum electrodes at high current density. (Figure presented.).
Electrochemical bromofunctionalization of alkenes in a flow reactor
Seitz, Jakob,Wirth, Thomas
supporting information, p. 6892 - 6896 (2021/08/20)
The bromination of organic molecules has been extensively studied to date, yet there is still a demand for safe and sustainable methodologies. Hazardous reagents, selectivity, low atom economy and waste production are the most persisting problems of brominating reagents. The electrochemical oxidation of bromide to bromine is a viable strategy to reduce waste by avoiding chemical oxidants. Furthermore, thein situgeneration of reactive intermediates minimizes the risk of hazardous reagents. In this work, we investigate the electrochemical generation of bromine from hydrobromic acid in a flow electrochemical reactor. Various alkenes could be converted to their corresponding dibromides, bromohydrines, bromohydrin ethers and cyclized products in good to excellent yields.
Continuous Flow Synthesis of Terminal Epoxides from Ketones Using in Situ Generated Bromomethyl Lithium
Von Keutz, Timo,Cantillo, David,Kappe, C. Oliver
supporting information, p. 10094 - 10098 (2019/12/24)
A scalable procedure for the direct preparation of epoxides from ketones has been developed. The method is based on the carefully controlled generation of (bromomethyl)lithium (LiCH2Br) from inexpensive CH2Br2 and MeLi in a continuous flow reactor. The reaction has shown excellent selectivity for a variety of substrates, including α-chloroketones, which typically fail under classic Corey-Chaykovsky conditions. This advantage has been used to develop a novel route toward the drug fluconazole.
Halofunctionalization of alkenes by vanadium chloroperoxidase from: Curvularia inaequalis
Dong, Jia Jia,Fernández-Fueyo, Elena,Li, Jingbo,Guo, Zheng,Renirie, Rokus,Wever, Ron,Hollmann, Frank
supporting information, p. 6207 - 6210 (2017/07/10)
The vanadium-dependent chloroperoxidase from Curvularia inaequalis is a stable and efficient biocatalyst for the hydroxyhalogenation of a broad range of alkenes into halohydrins. Up to 1 200 000 TON with 69 s-1 TOF were observed for the biocatalyst. A bienzymatic cascade to yield epoxides as reaction products is presented.
Halohydrin and its derivatives low priced high-efficient synthetic method (by machine translation)
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Paragraph 0092; 0093; 0094; 0095, (2017/08/25)
The invention discloses a halohydrin low priced high-efficient synthetic method, the organic solvent of formula I shown in the olefin compound with a halide, sulfoxide and additive mixing, by the olefin of hydroxy halogenate reaction, can be a high selectivity of the halohydrin the system results in the type II shown, wherein R1 , R2 , R3 , R4 , R5 And R6 Are selected from hydrogen, halogen, alkyl, hydroxyalkyl, alkoxy, ester, acyl, amido, dialkyl amino, aryl, substituted aromatic, heterocyclic aromatic group or substituted heterocyclic aromatic, R1 , R2 , R3 , R4 , R5 And R6 The presence of the respective independent may be identical or different; or R1 And R2 , R1 And R3 , R2 And R4 , R3 And R4 , R5 And R6 Combining to form a cycloalkyl or substituted cycloalkyl, benzo ring alkyl or substituted cycloalkyl, heterocycle or substituted heterocycle; M selected from hydrogen, lithium, sodium, potassium, cesium, beryllium, magnesium, calcium, strontium, barium, zinc, copper, iron, ammonium or tetraalkyl ammonium; X chlorine, bromine or iodine. (by machine translation)
Transformation of tertiary benzyl alcohols into the vicinal halo-substituted derivatives using N-Halosuccinimides
Ajvazi, Njomza,Stavber, Stojan
supporting information, (2016/11/02)
The efficiency of direct conversion of tertiary alcohols bearing a-hydrogen atom to vicinal halohydrins-chlorohydrins and bromohydrins-under green reaction conditions was tested preliminarily on modeltertiary benzyl alcohols. Tertiary alcohols were successfully directly halogenated to vicinal halohydrins with N-halosuccinimide in aqueous media. The efficiency of the reaction in water was significantly improved in the presence of sodium dodecyl sulphate as the surfactant.
Amino-functionalized (meth)acryl polymers by use of a solvent-polarity sensitive protecting group (Br-t-BOC)
Ritter, Helmut,Tabatabai, Monir,Herrmann, Markus
, p. 245 - 252 (2016/04/05)
We describe the synthesis of bromo-tert-butyloxycarbonyl (Br-t-BOC)-amino-protected monomers 2-((1-bromo-2-methylpropan-2-yl)oxycarbonylamino)ethyl (meth)acrylate 3a,b. For this purpose, 2-isocyanatoethyl (meth)acrylate 1a,b was reacted with 1-bromo-2-methylpropan-2-ol (2a). The free radical polymerization of (Br-t-BOC)-aminoethyl (meth)acrylates 3a,b yielded poly((Br-t-BOC)-aminoethyl (meth)acrylate) 6a,b bearing protected amino side groups. The subsequent solvolysis of the Br-t-BOC function led to the new polymers poly(2-aminoethyl (meth)acrylate) 8a,b with protonated free amino groups. The monomers and the resulting polymers were thoroughly characterized by 1H NMR, IR, GPC and DSC methods. The kinetics of the deprotection step was followed by 1H NMR spectroscopy. The solvent polarity and neighboring group effects on the kinetics of deprotection are discussed.
On the bromination of aromatics, alkenes and alkynes using alkylammonium bromide: Towards the mimic of bromoperoxidases reactivity
Mendoza, Fabian,Ruíz-Guerrero, Rosario,Hernández-Fuentes, Carlos,Molina, Paulina,Norzagaray-Campos, Mariano,Reguera, Edilso
supporting information, p. 5644 - 5648 (2016/11/28)
This article describes an efficient method of bromination of organic substrates including aromatics, alkenes and alkynes with NH4VO3as a catalyst and H2O2as an oxidant agent using a non-toxic and easy-to-handle source of bromine, tetrabutylammonium bromide. The process was developed under mild reaction conditions and is an innovation from reported methods in aspects such as: i) short reaction times, ii) the ability to work at room temperature, iii) regioselectivity and good yields.
Bromination of olefins with HBr and DMSO
Karki, Megha,Magolan, Jakob
, p. 3701 - 3707 (2015/04/22)
A simple and inexpensive methodology is reported for the conversion of alkenes to 1,2-dibromo alkanes via oxidative bromination using HBr paired with dimethyl sulfoxide, which serves as the oxidant as well as cosolvent. The substrate scope includes 21 olefins brominated in good to excellent yields. Three of six styrene derivatives yielded bromohydrins under the reaction conditions.
From simple organobromides or olefins to highly value-added bromohydrins: A versatile performance of dimethyl sulfoxide
Song, Song,Huang, Xiaoqiang,Liang, Yu-Feng,Tang, Conghui,Li, Xinwei,Jiao, Ning
supporting information, p. 2727 - 2731 (2015/05/27)
A novel and efficient direct transformation of secondary bromides or olefins to highly value-added bromohydrins has been disclosed. Dimethyl sulfoxide (DMSO), a cheap and common solvent, performs its versatile role as a solvent, an essential oxidant, and also as an oxygen source in this bromohydrin synthesis.
