- One pot synthesis of aryl nitriles from aromatic aldehydes in a water environment
-
In this study, we found a green method to obtain aryl nitriles from aromatic aldehyde in water. This simple process was modified from a conventional method. Compared with those approaches, we used water as the solvent instead of harmful chemical reagents. In this one-pot conversion, we got twenty-five aryl nitriles conveniently with pollution to the environment being minimized. Furthermore, we confirmed the reaction mechanism by capturing the intermediates, aldoximes.
- Chen, Qingqing,Han, Hongwei,Lin, Hongyan,Ma, Xiaopeng,Qi, Jinliang,Wang, Xiaoming,Yang, Yonghua,Zhou, Ziling
-
p. 24232 - 24237
(2021/07/29)
-
- Iodine Promoted Conversion of Esters to Nitriles and Ketones under Metal-Free Conditions
-
We report a novel strategy to prepare valuable nitriles and ketones through the conversion of esters under metal-free conditions. By using the I2/PCl3 system, various substrates including aliphatic and aromatic esters could react with acetonitrile and arenes to afford the desired products in good to excellent yields. This method is compatible with a number of functional groups and provides a simple and practical approach for the synthesis of nitrile compounds and aryl ketones.
- Xiao, Jing,Guo, Fengzhe,Li, Yinfeng,Li, Fangshao,Li, Qiang,Tang, Zi-Long
-
p. 2028 - 2035
(2021/02/03)
-
- 3,4- Difluorobenzonitrile process production method (by machine translation)
-
The invention relates to the field, of compound production technologies, in particular to 3,4 - difluoro-benzonitrile, obtained by centrifugally separating :S1: by adding raw material :S2: and removing toluene :S3: from the catalyst :S4: to collect the crude 3,4 - difluoro-cyanobenzene.S5: The reaction rate :S6: can be effectively reduced by controlling the presence time 3,4 - of the reaction depth. difluorobenzonitrile, by controlling the reaction depth of the system. N - The method (89.0 - 89.5%), comprises the following steps) - 1,3 - and, effectively reducing the coking, phenomenon, of the system at a high, temperature. The product. yield, is effectively reduced (3,4 . (by machine translation)
- -
-
Paragraph 0034-0038
(2020/02/27)
-
- A kind of boron-containing compounds and their use in catalytic fluorination reaction (by machine translation)
-
The invention relates to the field of fine chemical engineering, in particular to boron-containing compounds and application thereof in catalytic fluorination reaction. The boron-containing compoundsprovided by the invention are used as a catalyst and can be fluorinated by further mild reaction. Compared with the prior art, the boron-containing compounds have the advantages of mild conditions andhigh efficiency of the fluorination reaction, novel catalysis principle, simplicity and convenience in operation, less pollution, low solvent cost and suitability for industrial production.
- -
-
Paragraph 0030-0033; 0046-0049
(2019/05/28)
-
- Palladium-Catalyzed Late-Stage Direct Arene Cyanation
-
Methods for direct benzonitrile synthesis are sparse, despite the versatility of cyano groups in organic synthesis and the importance of benzonitriles for the dye, agrochemical, and pharmaceutical industries. We report the first general late-stage aryl C–H cyanation with broad substrate scope and functional-group tolerance. The reaction is enabled by a dual-ligand combination of quinoxaline and an amino acid-derived ligand. The method is applicable to direct cyanation of several marketed small-molecule drugs, common pharmacophores, and organic dyes. Benzonitriles are some of the most versatile building blocks for organic synthesis, in particular in the pharmaceutical industry, but general methods to make them by direct C–H functionalization are unknown. In this issue of Chem, Ritter and coworkers describe a late-stage aryl C–H cyanation with broad substrate scope and functional-group tolerance, enabled by a palladium-dual-ligand catalyst system. The reaction may serve for the late-stage modification of drug candidates. Aryl nitriles constitute an important class of organic compounds that are widely found in natural products, pharmaceuticals, agricultural chemicals, dyes, and materials. Moreover, nitriles are versatile building blocks to access numerous other important molecular structure groups. However, no general method for direct aromatic C–H cyanation is known. All approaches to date require either an appropriate directing group or reactive electron-rich substrates, such as indoles, which limit their synthetic applications. Here we describe an undirected, palladium-catalyzed late-stage aryl C–H cyanation reaction for the synthesis of complex aryl nitriles that would otherwise be more challenging to produce. The wide substrate scope and good functional-group tolerance of this reaction provide direct and quick access to structural diversity for pharmaceutical and agrochemical development.
- Zhao, Da,Xu, Peng,Ritter, Tobias
-
supporting information
p. 97 - 107
(2019/01/21)
-
- 3,4-difluorobenzonitrile preparation method
-
The invention discloses a 3,4-difluorobenzonitrile preparation method. The 3,4-difluorobenzonitrile preparation method comprises the following steps of taking 3,4-difluorobenzonitrile as a raw material, potassium fluoride as a fluorinated reagent and bis-(N,N'-1,3-dimethyl-2-imidazolinyl)-chloride ammonium salt as a phase transfer catalyst, then adding a reducing agent and a dispersant, and performing reaction to prepare the 3,4-difluorobenzonitrile. In the method, the temperature of fluorination reaction is relatively low, the reaction time is short, the total molar yield can reach about 90 percent, and the solvents and the catalyst can be recycled; produced potassium chloride in reaction becomes a pure product with the purity being 99 percent or above after recrystallization, and the pure product can be directly sold, so that the production cost is reduced; in addition, the technology is safe and environmentally friendly, is small in quantities of three wastes (waste water, waste solid and waste gas) and is suitable for industrial production.
- -
-
Paragraph 0045; 0048; 0051; 0053-0054; 0057; 0060; 0062
(2018/09/11)
-
- A 3, 4 - difluoro phenyl nitrile synthesis process
-
The invention discloses a process for synthesizing 3,4-difluorobenzonitrile. According to the process, 3,4-difluorobenzonitrile with the purity of over 99% is obtained through taking 3,4-dichlorobenzonitrile as a raw material, taking potassium fluoride as a fluorination reagent, taking 1,3-dimethyl-2-imidazolidinone as a reaction solvent, taking bis-(N-bis(dimethylamino)methylene)-iminium chloride as a catalyst, enabling reactants to react for 2-3 hours at the temperature of 130-150 DEG C and react for 5-6 hours at the temperature of 180-200 DEG C, then ending reaction, filtering a reaction solution and then rectifying under reduced pressure, and the yield can reach 85%. Rectification mother liquor (containing the catalyst) is mechanically applied to next-batch reaction directly. According to the process disclosed by the invention, the raw material is easy to obtain, the reaction conditions are mild, the reaction time is short, the operation is simple, the yield is high, the reaction solvent (containing the catalyst) can be repeatedly applied mechanically, the cost is low, and the emission of waste gases, waste water and waste residues is little, so that the process is applicable to industrial production.
- -
-
Paragraph 0040-0043
(2017/11/16)
-
- Continuous production method for industrially preparing 2,3-difluorobenzotrifluoride and 3,4-difluorobenzonitrile
-
The invention discloses a continuous production method for industrially preparing 2,3-difluorobenzotrifluoride and 3,4-difluorobenzonitrile. The preparation process of the 2,3-difluorobenzotrifluoride comprises the preparation step of an intermediate raw material for benzene sulfonamide and benzenesulfonylurea herbicides, and the preparation process of the 3,4-difluorobenzonitrile comprises the preparation step of a cthalofop-butyl intermediate raw material. The method is suitable for industrial production; and compared with the prior art, the method has the advantages of low cost, high production method and less pollution.
- -
-
Paragraph 0033
(2018/03/24)
-
- Decarbonylative Cyanation of Amides by Palladium Catalysis
-
Transition-metal-catalyzed cyanation of aryl halides is a process of significant importance in the preparation pharmaceuticals, organic materials and agrochemicals. Here, we demonstrate a palladium-catalyzed decarbonylative cyanation of amides by highly selective carbon-nitrogen bond cleavage for the synthesis of a wide range of aryl nitriles. The utility of this technology is demonstrated by the synthesis of isotopically labeled aryl nitriles and orthogonal cross-coupling reactions of bench-stable amides to establish cross-coupling synthons with opposite polarity.
- Shi, Shicheng,Szostak, Michal
-
supporting information
p. 3095 - 3098
(2017/06/23)
-
- 3,4-difluorobenzene nitrile method for the preparation of
-
The invention discloses a 3, 4-difluorobenzonitrile preparation method comprising the following steps: (1) reacting 1, 2-difluorobenzene with trichloroacetic chloride in the presence of a lewis acid catalyst at 0-40 DEG C for synthesis of 3, 4-difluoro-(alpha, alpha, alpha-trichloroacetic) benzene; (2) reacting the 3, 4-difluoro-(alpha, alpha, alpha-trichloroacetic) benzene with ammonia at -10-60 DEG C to obtain 3, 4-difluorobenzamide; (3) reacting the 3, 4-difluorobenzamide with a halogen-containing dehydration reagent and a catalyst at 30-80 DEG C to obtain 3, 4-difluorobenzonitrile. The 3, 4-difluorobenzonitrile preparation method overcomes the defects that in the prior art the raw material price is high, intermediates are highly toxic, reaction conditions are harsh, the reaction yield is poor, the purity is low, and the like, and is a 3, 4-difluorobenzonitrile synthesis process having the advantages of being easy to industrialization, simple in operation, high in yield and high in product purity.
- -
-
Paragraph 0029; 0032; 0033
(2017/04/07)
-
- Copper-catalyzed aerobic oxidative cleavage of C-C bonds in epoxides leading to aryl nitriles and aryl aldehydes
-
Novel copper-catalyzed aerobic synthesis of aryl nitriles and aldehydes from epoxides via C-C single bond cleavage has been discovered. This reaction provides a practical method toward the synthesis of aryl nitriles and aldehydes, which are versatile intermediates and building blocks in organic synthesis. This journal is
- Gu, Lijun,Jin, Cheng
-
supporting information
p. 6572 - 6575
(2015/04/14)
-
- The N-chlorination of primary amines using FeCl3 and m-CPBA
-
A simple and effective method for the synthesis of N,Ndichloroamines from primary amines was conducted successfully with m-CPBA as oxidant and FeCl 3 as chlorine source at 0 °C. Moreover, N,N-dichloroamines could be converted into nitriles or N-chloroimines in good yields.
- Liu, Jia,Xu, Junchao,Ren, Jiangmeng,Zeng, Bu-Bing
-
supporting information
p. 190 - 192
(2014/03/21)
-
- Elemental fluorine Part 12. Fluorination of 1,4-disubstituted aromatic compounds
-
Direct fluorination of a series of 1,4-disubstituted benzene derivatives in acid reaction media at convenient temperature leads, in many cases, to selectively fluorinated aromatic products in preparatively useful conversions and yields.
- Chambers, Richard D.,Hutchinson, John,Sparrowhawk, Matthew E.,Sandford, Graham,Moilliet, John S.,Thomson, Julie
-
p. 169 - 173
(2007/10/03)
-
- The effect of basicity on fluorodenitration reactions using tetramethylammonium salts
-
The fluorodenitration of several nitroaromatics with tetramethylammonium salts has been found to be dependent on the basicity of the fluorinating species. Tetramethylammonium fluoride is highly basic and is capable of inducing H-D exchange in 1,3-dinitrobenzene, as well as deprotonating N,N- dimethylacetamide. Reaction of the fluoride with phthalic anhydride forms the bifluoride in situ. Tetramethylammonium bifluoride gives higher yields of the required fluoroaromatic, but slower reaction rates than the corresponding fluoride.
- Adams, Dave J.,Clark, James H.,Nightingale, David J.
-
p. 7725 - 7738
(2007/10/03)
-
- SYNTHESIS OF 3,4-DIFLUOROBENZONITRILE AND MONOFLUOROBENZONITRILES BY MEANS OF HALOGEN-EXCHANGE FLUORINATION
-
3,4-Difluorobenzonitrile has been prepared by a halogen-exchange reaction between 3,4-dichlorobenzonitrile and spraydried potassium fluoride in the presence of tetraphenylphosphonium bromide in refluxing 1,3-dimethylimidazolidine-2-one.In the fluorination reaction, 4-chloro-3-fluorobenzonitrile seems to be a key intermediate. 3,4-Difluorobenzonitrile, 2-, 3-, and 4-fluorobenzonitriles have also been produced from the corresponding chlorobenzonitrile derivatives by halogen-exchange at 290 deg C, in DMI in a pressure reactor.
- Suzuki, Hiroshi,Kimura, Yoshikazu
-
p. 341 - 351
(2007/10/02)
-
- General and Highly Efficient Syntheses of m-Fluoro Arenes Using Potassium Fluoride-Exchange Method
-
Tetraphenylphosphonium bromide was found to be a suitable catalyst for the reaction of m-nitroaryl derivatives carrying cyano, nitro, chlorocarbonyl, trifluoromethyl, and chlorosulfonyl groups with potassium fluoride in the presence of a stoichiometric amount of phthaloyl dichloride, giving the corresponding m-fluoro aromatic derivatives in good yields.The catalyst was also found to be efficient for the fluorodesulfonylation of m-(fluorosulfonyl)aryl derivatives to afford m-fluoro arenes by the use of a reaction-distillation technique.
- Suzuki, Hiroshi,Yazawa, Naoto,Yoshida, Yasuo,Furusawa, Osamu,Kimura, Yoshikazu
-
p. 2010 - 2017
(2007/10/02)
-
- AROMATIC FLUORINE CHEMISTRY. PART 1. 3,4-DIFLUOROBENZOIC ACID AND DERIVATIVES VIA 3,4-DIFLUOROBENZOTRIFLUORIDE
-
The preparation of 3,4-difluorobenzotrifluoride from 3,4-dichlorobenzotrifluoride by a KF exchange reaction is described.The conversion of 3,4-difluorobenzotrifluoride to 3,4-difluorobenzoic acid and derivatives is also reported.
- Pews, R. G.,Gall, J. A.,Little, J. C.
-
p. 365 - 370
(2007/10/02)
-
- Tetraphenylphosphonium Bromide Catalyzed Fluorodenitrations and Fluorodesulfonylations. Efficient Syntheses of m-Fluoroaromatic Compounds
-
Meta-fluoroaromatic compounds were effectively synthesized from m-nitroaromatic or m-fluorosulfonylaromatic compounds by replacement reaction with potassium fluoride in the presence of a catalytic amount of tetraphenylphosphonium bromide.
- Yazawa, Naoto,Suzuki, Hiroshi,Yoshida, Yasuo,Furusawa, Osamu,Kimura, Yoshikazu
-
p. 2213 - 2216
(2007/10/02)
-