- A metal-free aerobic oxidative bromination of anilines and aryl ketones with 2-methylpyridinium nitrate as a reusable ionic liquid
-
An aerobic oxidative bromination of anilines and aryl ketones catalyzed by recyclable 2-methylpyridinium nitrate ionic liquid is achieved in water using hydrobromic acid as the bromine source and molecular oxygen as the oxidant. The catalytic system shows good efficiency and atom economy.
- Li, Ming-Fang,Wang, Jian,Ke, Yong-Xin,Pan, Song-Cheng,Yin, Hong,Du, Wenting,Li, Jing-Hua
-
p. 267 - 270
(2020/01/08)
-
- Sodium sulfate-hydrogen peroxide-sodium chloride adduct: selective protocol for the oxidative bromination, iodination and temperature dependent oxidation of sulfides to sulfoxides and sulfones
-
The regioselective bromination and iodination of unprotected aromatic primary amines using enclathrated hydrogen peroxide as an oxidant under mild conditions has been developed, in which potassium bromide (KBr) and potassium iodide (KI) were used as brominating and iodinating agents, respectively. The adduct shows not only regioselectivity for para- or ortho-isomers but also a remarkable chemoselectivity for monobromination. Selective oxidation of sulfides to sulfoxides and sulfones has also been studied and good to excellent yields of the desired products were obtained. Acetic acid was found to be the solvent of choice for these reactions. This simple method represents an ecologically benign and alternative pathway for the oxidative halogenation of anilines and the oxidation of sulfides to sulfoxides and sulfones.
- Gayakwad, Eknath M.,Patel, Khushbu P.,Shankarling, Ganapati S.
-
supporting information
p. 6001 - 6009
(2019/04/17)
-
- Cu-mediated selective bromination of aniline derivatives and preliminary mechanism study
-
A simple and efficient bromination of aniline, aniline derivatives, and analogs have been developed. Forty three examples were given and the highest yield reached was 98%. Different substrates including substituted aniline, pyridin-amine, N-substituted aniline, N,N-disubstituted aniline, N-phenyl-amide, N-phenyl-sulfonamide, and nitrogen-containing heterocycles were all reactive and selectively generated desired bromo-products. The method can be applied to synthesize drug intermediate and quinoxaline derivatives.
- Zhao, Hong-Yi,Yang, Xue-Yan,Lei, Hao,Xin, Minhang,Zhang, San-Qi
-
supporting information
p. 1406 - 1415
(2019/05/01)
-
- o-xylylene bis(triethyl ammonium tribromide) as a mild and recyclable reagent for rapid and regioselective bromination of anilines and phenols
-
Background: o-Xylylene bis(triethyl ammonium tribromide) (OXBTEATB) as a recyclable and high bromine containing di-(tribromide) reagent has been employed for the bromination of various organic substrates such as phenol and aniline or its derivatives. This catalyst can be recovered and reused several times. Methods: Aryl bromides shown in Table 1, were easily produced from bromination of aromatic compounds by OXBTEATB. This high-yield process lets the reagents to be recycled and reused. Results: As shown in Table 1, substituted anilines, phenols and β-naphthol were found to be the most reactive and immediately converted to the corresponding mono-brominated products by OXBTEATB. Conclusion: OXBTEATB can be considered a solidified bromine. This novel reagent has variable solubility in different polar protic and aprotic solvents but insoluble in non-polar aprotic solvent. Subsequently, OXBTEATB can be recognized as a more useful brominating and regioselective catalyst than the liquid bromine.
- Hemati, Roya,Shahvelayati, Ashraf S.,Yadollahzadeh, Khadijeh
-
p. 682 - 687
(2018/07/14)
-
- Preparation method of SGLT2 inhibitor-empagliflozin
-
The invention relates to a preparation method of a SGLT2 inhibitor-empagliflozin. The preparation method includes: using 2-methylaniline as a starting raw material, subjecting the starting raw material to bromination, diazotization, chlorination and bromination, and enabling the starting raw material to be in friedel-crafts alkylation reaction with (S)-3-phenoxy tetrahydrofuran to obtain an intermediate-(S)-3-(4-(5-bromo-2-chlorobenzyl)phenoxy) tetrahydrofuran; subjecting the intermediate and 2, 3, 4, 6-tetra-O-trimethylsilyl-D-glucolactone to condensation, etherification and methoxy removal.The preparation method has the advantages that compared with existing synthetic methods, 2-methylaniline is used as the starting raw material, so that the raw material is low in cost and easy to get,the process is easy for industrialization, and a synthetic route is short and easy to operate; in the process of preparation, temperature conditions are easy to control, reaction conversion rate is high, and total yield is up to higher than 75%. In addition, through the preparation method, the inhibitor is less prone to isomerization, impurities are few, and purity of the inhibitor can be improvedto higher than 99%.
- -
-
Paragraph 0015; 0016
(2018/03/26)
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- Chemoselective Deprotection of Sulfonamides under Acidic Conditions: Scope, Sulfonyl Group Migration, and Synthetic Applications
-
Chemoselective acidic hydrolysis of sulfonamides with trifluoromethanesulfonic acid has been evaluated as a deprotection method and further extended to more complex synthetic applications. In contrast to conventional troublesome sulfonamide hydrolysis, a near-stoichiometric amount of acid was found to be sufficient to bring about efficient deprotection of various neutral or electron-deficient N-arylsulfonamides, whereas electron-rich substrates provided sulfonyl group migration products. The deprotection method developed is fully selective for N-arylsulfonamides, and the possibility to discriminate among various different sulfonamides is demonstrated.
- Javorskis, Tomas,Orentas, Edvinas
-
p. 13423 - 13439
(2017/12/26)
-
- 5-bromo-2-chloro -4 the-oxethyl diphenylmothane [...] preparation method
-
The invention relates to the chemical field and particularly relates to a novel synthesis method for preparing a key intermediate 5-bromine-2-chlorine-4'-ethyoxyl diphenylmethane of a drug dapagliflozin for treating diabetes mellitus II. The preparation method comprises the following steps: enabling a starting raw material ortho-toluidine to firstly perform bromization and then perform chlorination after diazotization on a benzene ring with N-bromo-succinimide; then, in the presence of a halogenating agent, performing halogenating reaction of beta-position; and finally, performing Friedel-Crafts alkylation synthesis with phenetole, thereby obtaining the key intermediate. The preparation method is simple and convenient, economical and relatively high in reaction yield in each step, and suitable for industrial production.
- -
-
Paragraph 0025-0026
(2017/04/03)
-
- Under the conditions of a solvent-free method of hydrogenation to synthesize haloarylamine
-
The invention provides a method for synthesising halogenated aromatic amine through hydrogenation in a solvent-free condition. The method comprises the following step of: carrying out a liquid-phase hydrogenation reaction on the halogenated aromatic nitro compound shown in formula (I) under the action of hydrogen, in the absence of a solvent and a dehalogenation inhibitor under the action of a carbon-supported large-particle-size precious metal catalyst to prepare the halogenated aromatic amine shown in formula (II). The method provided by the invention is capable of achieving the effect of inhibiting a hydrogenation dehalogenation side reaction in the case of not adding a dehalogenation inhibitor, is high in target product selectivity, and is capable of remarkably increasing the reaction speed.
- -
-
Paragraph 0050-0053
(2017/03/21)
-
- Para-Selective Halogenation of Nitrosoarenes with Copper(II) Halides
-
The para-selective direct bromination and chlorination of nitrosoarenes with copper(II) bromide and chloride is reported. Under mild reaction conditions, a range of halogenated arylnitroso compounds are obtained in moderate to good yields with high regioselectivity. Additionally, the versatility of the method is demonstrated by the development of a one-pot procedure to obtain the corresponding para-halogenated aniline- and nitrobenzene derivatives.
- Van Der Werf, Angela,Selander, Nicklas
-
supporting information
p. 6210 - 6213
(2016/01/09)
-
- New insights into bromination process: Effective preparation of Ambroxol
-
Ambroxol used as an expectorant in treating respiratory diseases was effectively prepared with a total yield of 62 %, with o-toluidine as the feedstock via successive procedures of electrophilic bromination, acetylation, radical benzylic bromination, N-alkylation and hydrolysis processes. The addition of aqueous hydrogen peroxide could enhance the utilisation of liquid bromine in the electrophilic bromination of o-toluidine, avoiding the hazardous HBr generated as a by-product. In addition, liquid bromine promoted by MnO2 was used efficiently for the radical benzylic bromination of N-acetyl-N-(2,4-dibromo-6-methylphenyl)acetamide under mild conditions.
- Xu, Jun-Hui,Ma, Yan-Qiong,Wei, Jian-Ping,Li, Fang-Mei,Peng, Xin-Hua
-
p. 722 - 728
(2015/04/14)
-
- Preparation of carbazole and dibenzofuran derivatives by selective bromination on aromatic rings or benzylic groups with N-bromosuccinimide
-
N-Bromosuccinimide (NBS), a bromine source, has been used to study the bromination of toluidine and cresols systematically to clarify the underlying mechanism and the orientation effect. It has been found that bromination of toluidine and cresols which possess electron-donating NH2/OH with NBS gives electrophilic aromatic substitution products quickly instead of the desired benzylic bromination products. In contrast, when the electronic effect of the substituted groups is reversed, only the benzylic bromination products are gained. Based on this methodology, several potential AChE inhibitors, such as 2-methoxy-5-(benzylamino)methyl-dibenzofuran, 3-bromo-2-methoxy-5-methyl-9H- carbazole, 3,6-dibromo-2-methoxy-5-methyl-9H-carbazole, and 5-(bromomethyl)-2- methoxy-9H-(phenylsulfonyl)-carbazole have been synthesized.
- Fang, Lei,Zhang, Haun,Fang, Xubin,Gou, Shaohua,Cheng, Lin
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p. 635 - 641
(2014/06/23)
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- NOVEL TRIAZINE COMPOUNDS
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The present invention relates to novel triazine compounds of formula (1). The present invention also discloses compounds of formula I along with other pharmaceutical ac-ceptable excipients and use of the compounds to modulate the PI3K/ mTOR pathway
- -
-
Page/Page column 119; 120
(2014/02/16)
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- Selective bromination of pyrrole derivatives, carbazole and aromatic amines with DMSO/HBr under mild conditions
-
Bromination of pyrrole derivatives, carbazole and aromatic amines using the DMSO/HBr system affords high yields of the corresponding bromo compounds. Temperature control used in the bromination of anilines helped to promote selective formation of mono- or di-brominated products. Simple operation, low toxicity and high selectivity make this a promising new procedure for the bromination of aromatic compounds.
- Liu, Cong,Dai, Rongji,Yao, Guowei,Deng, Yulin
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p. 593 - 596
(2015/01/09)
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- Aerobic oxidation and oxidative bromination in aqueous medium using polymer anchored oxovanadium complex
-
Polymer anchored oxovanadium catalyst was synthesized and characterized. Its catalytic activity was evaluated for the oxidation of various primary and secondary alcohols with molecular oxygen under mild reaction conditions. This catalyst was also effective for the oxidative bromination reaction of organic substrates with 90-100% selectivity of mono substituted products with H 2O2/KBr at room temperature. The above reactions require low temperature, short time period and most importantly all the above reactions occur in aqueous medium. The developed catalyst can be facilely recovered and reused six times without significant decrease in activity and selectivity. 2014 Elsevier B.V. All rights reserved.
- Islam, Sk. Manirul,Molla, Rostam Ali,Roy, Anupam Singha,Ghosh, Kajari,Salam, Noor,Iqubal, Md. Asif,Tuhina
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p. 169 - 178
(2014/05/06)
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- A facile, regioselective and controllable bromination of aromatic amines using a CuBr2/Oxone system
-
A combination of cupric bromide and Oxone serves as a facile, mild and effective reagent for the bromination of aromatic amines. Primary, secondary and tertiary aromatic amines are all suitable substrates. The reaction possesses high regioselectivity and functional group tolerance, and mono- and multi-brominated products can be obtained controllably in moderate to excellent yields. The Royal Society of Chemistry 2013.
- Li, Xin-Le,Wu, Wei,Fan, Xin-Heng,Yang, Lian-Ming
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p. 12091 - 12095
(2013/09/02)
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- Selective oxidation of sulfides and oxidative bromination of organic substrates catalyzed by polymer anchored Cu(II) complex
-
A new polymer-anchored Cu(II) complex has been synthesized and characterized. The catalytic performance of the complex has been tested for the oxidation of sulfides and in oxidative bromination reaction with hydrogen peroxide as the oxidant. Sulfides have been selectively oxidized to the corresponding sulfoxides in excellent yields and in the presence of KBr as the bromine source, organic substrates have been selectively converted to mono bromo substituted compounds using polymer-anchored Cu(II) catalyst. This catalyst showed excellent catalytic activity, high selectivity, and recyclability. The polymer-anchored Cu(II) catalyst could be easily recovered by filtration and reused more than five times without appreciable loss of its initial activity.
- Islam,Roy, Anupam Singha,Mondal, Paramita,Tuhina, Kazi,Mobarak, Manir,Mondal, John
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supporting information; experimental part
p. 127 - 131
(2012/01/17)
-
- Regioselective chlorination and bromination of unprotected anilines under mild conditions using copper halides in ionic liquids
-
By using ionic liquids as solvents, the chlorination or bromination of unprotected anilines at the para-position can be achieved in high yields with copper halides under mild conditions, without the need for potentially hazardous operations such as supplementing oxygen or gaseous HCl.
- Wang, Han,Wen, Kun,Nurahmat, Nurbiya,Shao, Yan,Zhang, He,Wei, Chao,Li, Ya,Shen, Yongjia,Sun, Zhihua
-
supporting information; experimental part
p. 744 - 748
(2012/06/30)
-
- Synthesis, catalytic oxidation and oxidative bromination reaction of a reusable polymer anchored oxovanadium(IV) complex
-
Polymer anchored oxovanadium catalyst was synthesized and characterized. The solid catalyst was characterized by Fourier transform infrared spectroscopy (FT-IR), UV-vis diffuse reflectance spectroscopy (DRS), thermogravimetric analysis (TGA) and scanning electron microscope (SEM). Its catalytic activity was evaluated for the oxidation of various alkenes, sulfides and aromatic alcohols with 30% H2O2 under mild reaction conditions. This catalyst was also effective for the oxidative bromination reaction of organic substrates with 80-100% selectivity of mono substituted products with H2O2/KBr at room temperature. The above reactions require minimum amount of H2O2, short time period and most importantly all the above reactions occur in aqueous medium. The developed catalyst can be facilely recovered and reused six times without significant decrease in activity and selectivity. This result confirms that the polymer anchored complex was not leached during the reaction, suggesting the true heterogeneous nature of the catalyst.
- Islam, Sk. Manirul,Roy, Anupam Singha,Mondal, Paramita,Salam, Noor
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experimental part
p. 38 - 48
(2012/05/21)
-
- Red-emitting dyes with photophysical and photochemical properties controlled by pH
-
New unsymmetrical zinc azaphthalocyanines, bearing one substituted aniline as a peripheral substituent, were prepared by using a statistical condensation approach. Both fluorescence and singlet oxygen quantum yields were extremely low in DMF (φFΔF=0. 22-0.29, φΔ=0.40-0.59, respectively). This behavior was attributed to the deactivation of excited states by intramolecular charge transfer from a donor site (aniline), which was blocked after protonation in acidic media. In the protonated form, all of the compounds efficiently emitted light with λem in the region of 662-675 nm. The investigated compounds were anchored to dioleoylphosphatidylcholine (DOPC) unilamellar vesicles and showed response to buffer pH. They were highly fluorescent at low pH values and almost nonfluorescent in neutral solutions. The pKa values were determined in DOPC vesicles and ranged between 2.2 and 4.2.
- Novakova, Veronika,Miletin, Miroslav,Kopecky, Kamil,Zimcik, Petr
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supporting information; experimental part
p. 14273 - 14282
(2012/01/06)
-
- SUBSTITUTED AROMATIC CARBOXAMIDE AND UREA DERIVATIVES AS VANILLOID RECEPTOR LIGANDS
-
The invention relates to substituted aromatic carboxamide and urea derivatives, to processes for the preparation thereof, to pharmaceutical compositions containing these compounds and also to the use of these compounds for preparing pharmaceutical compositions (formula (I)).
- -
-
Page/Page column 118; 119
(2010/11/18)
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- Silica-supported quinolinium tribromide: A recoverable solid brominating reagent for regioselective monobromination of aromatic amines
-
Silica-supported quinolinium tribromide was synthesized and found to be an efficient, stable, and recoverable solid brominating reagent for the regioselective monobromination of aromatic amines. This protocol has advantages of high yield, mild condition and simple work-up procedure.
- Li, Zheng,Sun, Xiunan,Wang, Lue,Li, Yanbo,Ma, Yuanhong
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scheme or table
p. 496 - 501
(2010/08/06)
-
- Regiospecific oxyhalogenation of aromatics over SBA-15-supported nanoparticle group IV-VI metal oxides
-
TiOx, VOx, MoOx and WOx supported on SBA-15 exhibit efficient catalytic activity for oxyhalogenation of aromatics with the H2O2-halide ion system. Unlike the hitherto known solid catalysts, these reusable catalysts yield the para-halogenated product with 100% selectivity at 298 K and moderate acidic pH (3-5). The catalytic activity was enhanced by five orders of magnitude when supported on SBA-15. Springer Science+Business Media, LLC 2010.
- Saikia,Rajesh,Srinivas,Ratnasamy
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scheme or table
p. 190 - 201
(2010/11/05)
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- Effect of structural factors and solvent nature in bromination of anilines
-
Reaction of electrophilic bromination of aniline containing various ortho, meta, and para substituents in the aromatic ring was studied. The optimal conditions for synthesis of mono-, di-, tri-, and tetrabromo derivatives of aniline and brominated analog of Aniline Black were found.
- Bagmanov
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experimental part
p. 1570 - 1576
(2011/06/20)
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- Simple catalyst-free regio- and chemoselective monobromination of aromatics using NBS in polyethylene glycol
-
NBS in polyethylene glycol has been efficiently utilized for regio- and chemoselective bromination of activated aromatics at room temperature to form the corresponding bromo products in excellent yields. Copyright Taylor & Francis Group, LLC.
- Venkateswarlu, Katta,Suneel, Kanaparthy,Das, Biswanath,Reddy, Kuravallapalli Nagabhushana,Reddy, Thummala Sreenivasulu
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experimental part
p. 215 - 219
(2009/04/07)
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- Structure-activity relationships of bioisosteres of a carboxylic acid in a novel class of bacterial translation inhibitors
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The discovery and initial optimization of a novel anthranilic acid derived class of antibacterial agents which suffered from extensive protein binding has been previously reported. The structure-activity relationships around the carboxylic acid substituent are described herein. This acid was replaced by several alternative functional groups in attempts to retain bioactivity while reducing protein binding. Only groups with an acidic proton retained activity, and analogs containing those groups maintained the protein binding inherent to this class of antibacterial agents.
- Ruble, J. Craig,Wakefield, Brian D.,Kamilar, Gregg M.,Marotti, Keith R.,Melchior, Earline,Sweeney, Michael T.,Zurenko, Gary E.,Romero, Donna L.
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p. 4040 - 4043
(2008/02/08)
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- An efficient, rapid and regioselective nuclear bromination of aromatics and heteroaromatics with NBS using sulfonic-acid-functionalized silica as a heterogeneous recyclable catalyst
-
A simple, efficient and rapid method has been developed for high-yielding regioselective nuclear monobromination of aromatic and heteroaromatic compounds using NBS in the presence of sulfonic-acid-functionalized silica at room temperature. The catalyst works under heterogeneous conditions and can be recycled.
- Das, Biswanath,Venkateswarlu, Katta,Krishnaiah, Maddeboina,Holla, Harish
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p. 8693 - 8697
(2007/10/03)
-
- Novel bromination method for anilines and anisoles using NH 4Br/H2O2 in CH3COOH
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A simple, efficient, regioselective, environmentally safe, and economical method for the oxybromination of anilines and anisoles without catalyst is reported. The electrophilic substitution of bromine generated in situ from ammonium bromide as a bromine source and hydrogen peroxide as an oxidant for the first time.
- Krishna Mohan,Narender,Srinivasu,Kulkarni,Raghavan
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p. 2143 - 2152
(2007/10/03)
-
- [bmim]Br3 as a new reagent for regioselective monobromination of arylamines under solvent-free conditions
-
Reaction of arylamines with 1-butyl-3-methylimidazolium tribromide ([bmim]Br3) under solvent-free conditions, gave selectively the corresponding monobromination products with excellent, yields.
- Le, Zhang-Gao,Chen, Zhen-Chu,Hu, Yi,Zheng, Qin-Guo
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p. 2809 - 2812
(2007/10/03)
-
- A new mild regioselective bromination of arylamines
-
A new efficient regioselective boron-assisted mono bromination methodology for arylamines is described. Our one-pot, three-stage approach (lithiation, boron amide formation and bromination) proved to be highly useful in mildly brominating a variety of arylamines in up to 94% yields.
- Zhao, Jingrui,Jia, Xueshun,Zhai, Hongbin
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p. 9371 - 9373
(2007/10/03)
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- Regioselective one-pot bromination of aromatic amines
-
(Matrix Presented) Treatment of aniline with n-butyllithium and then trimethyltin chloride gave the tin amide (PhNH-SnMe3) in situ. Without isolation of the tin amide reaction with bromine and workup with aqueous fluoride ion gave p-bromoaniline in 76% yield, with no dibromoaniline or o-bromoaniline. Application of this sequence to 11 different aromatic amines gave selective bromination in 36-91% yields, without formation of dibromides. This constitutes a good general method for the regioselective bromination of aromatic amines.
- Smith, Michael B.,Guo, Lisa,Okeyo, Sherrad,Stenzel, Jason,Yanella, James,LaChapelle, Eric
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p. 2321 - 2323
(2007/10/03)
-
- Liquid phase regioselective bromination of aromatic compounds over HZSM-5 catalyst
-
A simple, efficient, regioselective and environmentally safe method for oxybromination of activated aromatics catalyzed by HZSM-5 is reported. The electrophilic substitution of bromine generated from KBr using HZSM-5 as a catalyst and H2O2 as an oxidant.
- Narender,Srinivasu,Kulkarni,Raghavan
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p. 3669 - 3675
(2007/10/03)
-
- Halide ion trapping of nitrenium ions formed in the Bamberger rearrangement of N-arylhydroxylamines. Lifetime of the parent phenylnitrenium ion in water
-
The data of p-aminophenol, the product of Bamberger rearrangement, Were analyzed by a mechanism involving rate-limiting formation of the appropriate arylnitrenium ion followed by product-determining steps in involving trapping by the solvent or by the added halide. The possibility that a portion of the halide-trapped products were derived from a pre-association mechanism was also include. Kinetic analyses then produced kBr:kw and kCl:kw ratios for two limiting cases, one involving pre-association with an equilibrium constant Kas = 0.3, and one ignoring pre-association. From an azide:water ratio (kAz:kw) previously determined for the 2,6-dimethylphenylnitrenium, kBr was concluded to lie in the range (4-5) × 109 M-1 s-1 for all of the nitrenium ions of this study. This range for kBr then led to kw values of (1-2) × 109 s-1 (2,5-Me2), (2-3) × 109 s-1 (2-Me), and (4-8) × 109 s-1 (parent and 2-Cl), where the ranges reflect uncertainties in the exact value of kBr and in the contribution from pre-association. The lifetime of the parent phenylnitrenium ion in water at one molar ionic strength is concluded to lie in the range 125-250 ps.
- Fishbein,McClelland
-
p. 1321 - 1328
(2007/10/03)
-
- Novel site-specific one-step bromination of substituted benzenes
-
Regiospecific bromination of benzene derivatives has been carried out with Me2SO-HBr; this method gives excellent yields of 2-bromobenzaldehyde and 2-bromonitrobenzene; strong ortho- and para-directing monosubstituted benzenes give para-bromo derivatives; a general discussion of the mechanism of these reactions is given.
- Srivastava, Sanjay K.,Chauhan, Prem Man Singh,Bhaduri, Amiya P.
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p. 2679 - 2680
(2007/10/03)
-
- Para-bromination of ortho-alkyl anilines
-
A process of selectively preparing p-bromo-o-alkylanilines (e.g. 4-bromo-2-methylaniline) by reacting o-alkylanilines (e.g., 2-methylaniline) with unadsorbed bromine in a solvent selected from the group consisting of an inert di- tri- or tetrahaloaliphatic hydrocarbon (e.g., dichloromethane and dibromomethane), an alkyl nitrile (e.g., acetonitrile) and mixtures thereof.
- -
-
-
- SELECTIVE MONOBROMINATION OF ANILINE DERIVATIVES BY USE OF BROMINE ADSORBED ON ZEOLITE 5A
-
Aniline is selectively brominated by use of molecular bromine adsorbed on zeolite 5A in carbon tetrachloride to give monobromoanilines.Coexistence of organic bases such as pyridine and 2,6-lutidine increases the yield and selectivity of 4-bromoaniline. o-, m-, and p-Toluidines are also monobrominated selectively according to the present procedure.
- Onaka, Makoto,Izumi, Yusuke
-
p. 2007 - 2008
(2007/10/02)
-