70288-97-0Relevant articles and documents
Visible-Light-Driven Oxidative Mono- and Dibromination of Benzylic sp 3 C-H Bonds with Potassium Bromide/Oxone at Room Temperature
Zhao, Mengdi,Li, Meiqi,Lu, Wenjun
supporting information, p. 4933 - 4939 (2018/12/14)
Benzylic sp 3 C-H bonds have been successfully brominated with potassium bromide by using Oxone as an oxidant in water/dichloromethane under visible light at room temperature. Toluene, ethylbenzene and other alkylbenzenes bearing an electron-withdrawing group, such as Br, Cl, COMe, CO 2 Et, CO 2 H, CN or NO 2, provide the corresponding benzylic monobromides in good to excellent yields in this reaction. Dibromides can also be produced in the presence of excess potassium bromide in a prolonged reaction time. Control of the illuminance of visible light (~500 lux) is crucial to achieving both high yield and high selectivity in these brominations. Mono- and difluorides can be conveniently prepared through nucleophilic substitutions of the benzylic bromides with potassium fluoride.
Method for preparing benzyl bromide
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Paragraph 0070-0072, (2017/10/05)
The invention provides a method for preparing benzyl bromide. The method comprises the following steps: by taking bromine released from a redox reaction between bromates and negative bromide ions in the presence of an acid as a bromine source in an organic solvent, carrying out a benzyl radical substitution reaction with a methylbenzene compound shown as a formula I under initiation of an initiator, thereby obtaining a corresponding benzyl bromide compound shown a formula II, wherein in the formula II, m represents the number of Br and is equal to 1 or 2; when m is equal to 1, the formula II shows a benzyl monobromo compound; and when m is equal to 2, the formula II shows a benzyl dibromo compound. The reaction is carried out in an organic solvent, the initiator is combined and used, the radical substitution reaction is high in selectivity and wide in substrate application range, the substituent group replacing methylbenzene may be an electron-withdrawing group or an electron-donating group and can give extremely high yield on strong electron-donating groups (such as methoxy group). Moreover, the method disclosed by the invention is also applicable to preparation of benzyl dibromo compounds, and the product yield is high.
Easy access for the synthesis of 2-aryl 2,3-dihydroquinazolin-4(1H)-ones using gem-dibromomethylarenes as synthetic aldehyde equivalent
Narasimhamurthy, Kereyagalahally H.,Chandrappa, Siddappa,Sharath Kumar, Kothanahally S.,Harsha, Kachigere B.,Ananda, Hanumappa,Rangappa, Kanchugarakoppal S.
, p. 34479 - 34486 (2014/10/16)
One step synthesis of 2,3-dihydroquinazolin-4(1H)-ones from gem-dibromomethylarenes using 2-aminobenzamide is described. Gem-dibromomethylarenes are used as aldehyde equivalent for the efficient synthesis of 2,3-dihydroquinazolin-4(1H)-ones, this synthesis takes shorter reaction time with quick isolation and excellent product yield. This journal is the Partner Organisations 2014.
TETRACYCLIC INDOLE DERIVATIVES FOR TREATING HEPATITIS C VIRUS INFECTION
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Page/Page column 189, (2012/04/17)
Tetracyclic indole derivatives of formula (I), pharmaceutically acceptable salts and the pharmaceutical compositions thereof are provided, wherein A, A', G, R1, R15, U, V, V, W, W, X, X', Y, Y' are as defined in the invention. Use of these derivatives for treating hepatitis C virus (HCV) infection is also provided.
High selectively oxidative bromination of toluene derivatives by the H 2O2-HBr system
Ju, Jie,Li, Yu Jin,Gao, Jian Rong,Jia, Jian Hong,Han, Liang,Sheng, Wei Jian,Jia, Yi Xia
scheme or table, p. 382 - 384 (2012/01/05)
An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine radicals. Various substituted toluenes (NO2, Cl, Br, H, CH3) were high selectively brominated at the benzyl position for monobromination in CH2Cl2 at ice water with catalyst free. This simple but effective bromination of toluene derivatives with an aqueous H2O 2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods.
A simple and efficient procedure for the preparation of benzal chlorides and benzal bromides
Léonel, Eric,Paugam, Jean-Paul,Heintz, Monique,Nédélec, Jean-Yves
, p. 4015 - 4024 (2007/10/03)
Benzal chlorides and benzal bromides were conveniently synthesized by reaction of aryl aldehydes with a Vilsmeier type reagent formed in situ by reduction of CCl4 or CBr4 in dimethylformamide (DMF) as solvent.
MECHANISMS OF FREE-RADICAL REACTIONS. XX. REACTIVITY IN THE FREE-RADICAL HALOGENATION REACTIONS OF ARYLFLUOROALKANES
Dneprovskii, A. S.,Eliseenkov, E. V.
, p. 711 - 719 (2007/10/02)
The free-radical chlorination and bromination of meta- and para-substituted benzyl fluorides and 1,1-difluoro-2-phenylethane and also the chlorination of 1-fluoro-2-arylethanes by phenylchloroiodonium chloride and the bromination of meta- and para-substituted benzyl bromides were studied by the method of competing reactions.In all cases a good correlation is observed between log krel and the Brown ?+ constants.In cases where change in the reactivity in the transition from one reaction series to another is due mainly to the polar effect of the substituent whilethe selectivity is measured in relation to the polar effect direct relationships are observed between the reactivity and the selectivity.
