- Method for preparing 2-bromo-5-fluoroaniline
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The invention discloses a method for preparing 2-bromo-5-fluoroaniline, belonging to the field of organic chemical synthesis. The preparation method comprises the following steps: with 4-fluoroanilineas a raw material, reacting 4-fluoroaniline with acetic anhydride to generate 4-fluoroacetanilide; performing nitrification; replacing acetamido groups with bromine; and reducing nitro groups. Thus,the 2-bromo-5-fluoroaniline with high yield and high purity is prepared. The method has the advantages of high product yield, high purity, easy availability of raw materials and simple operation, andis beneficial to industrial production.
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Paragraph 0039; 0043; 0046; 0050; 0055; 0059
(2020/12/31)
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- A preparation method for 4-methoxy-2-nitrobenzoic acid
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An industrial preparation method for 4-methoxy-2-nitrobenzoic acid is disclosed. In the method, p-difluorobenzene is adopted as an initial raw material and subjected to nitration, ammonolysis, diazotization bromination, cyaniding, methoxylation and hydrolysis which are six steps to synthesize the 4-methoxy-2-nitrobenzoic acid. The 4-methoxy-2-nitrobenzoic acid obtained by the method is white powdered solid with purity being 98.5%, the raw material conversion ratio in each step is 100%, and the total yield of the whole process is 35.8%.
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Paragraph 0014; 0016; 0017; 0021; 0023; 0024
(2019/04/26)
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- Inexpensive NaX (X = I, Br, Cl) as a halogen donor in the practical Ag/Cu-mediated decarboxylative halogenation of aryl carboxylic acids under aerobic conditions
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Versatile and practical Ag/Cu-mediated decarboxylative halogenation between readily available aryl carboxylic acids and abundant NaX (X = I, Br, Cl) has been achieved under aerobic conditions in moderate to good yields. The halodecarboxylation is shown to be an effective strategy for S-containing heteroaromatic carboxylic acid and benzoic acids with nitro, chloro and methoxyl substituents at the ortho position. A gram-scale reaction and a three-step procedure to synthesize iniparib have been performed to evaluate the practicality of this protocol. A preliminary mechanistic investigation indicates that Cu plays a vital role and a radical pathway is involved in the transformation.
- Fu, Zhengjiang,Jiang, Ligao,Zuo, Qianming,Li, Zhaojie,Liu, Yanzhu,Wei, Zhenhong,Cai, Hu
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supporting information
p. 5416 - 5421
(2018/08/12)
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- Synthesis method of 2-bromo-5-fluoronitrobenzene
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The invention discloses a synthesis method of 2-bromo-5-fluoronitrobenzene and belongs to the field of organic chemistry. The synthesis method comprises the steps: adding m-nitrofluorobenzene and dibromohydantoin into an organic solvent, carrying out heating, dropwise adding a sulfuric acid aqueous solution, carrying out a further heat insulation reaction after finishing dropping, and then, carrying out cooling to room temperature; separating an organic layer, carrying out washing to be neutral, and then, carrying out reduced-pressure desolvation to obtain a target product. A reaction system of the method is simple, raw materials are available, the sulfuric acid aqueous solution can be indiscriminately used many times, the wastewater content is low, and a simple and green approach is provided for the synthesis of the compound.
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Paragraph 0039-0042
(2018/11/22)
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- Synthetic method of aryl halide taking aryl carboxylic acid as raw material
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A synthetic method of an aryl halide taking aryl carboxylic acid as a raw material is characterized in that a corresponding aryl halide is formed by carrying out substitution reaction on an aryl carboxylic acid compound and haloid salt MX in an organic solvent under the condition that oxygen, a silver catalyst, a copper additive and a bidentate nitrogen ligand exist, wherein M in MX represents alkali metal or alkaline earth metal, and X represents F, Cl, Br or I. Compared with a conventional aryl halide synthetic method, the synthetic method disclosed by the invention has the obvious advantages that reaction raw materials (comprising aryl carboxylic acid and MX) are cheap and easy to obtain, the using amount of a metal catalyst is small, pollution to the environment when the oxygen is used as an oxidant is the smallest, good tolerance to various functional groups on an aromatic ring is obtained, the yield is high, and the like. The synthetic method disclosed by the invention can be widely applied to synthesis in the fields of medicine, materials, natural products and the like in industry and academia.
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Paragraph 0067
(2018/01/03)
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- Decarboxylative Halogenation and Cyanation of Electron-Deficient Aryl Carboxylic Acids via Cu Mediator as Well as Electron-Rich Ones through Pd Catalyst under Aerobic Conditions
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Simple strategies for decarboxylative functionalizations of electron-deficient benzoic acids via using Cu(I) as promoter and electron-rich ones by employing Pd(II) as catalyst under aerobic conditions have been established, which lead to smooth synthesis of aryl halides (-I, Br, and Cl) through the decarboxylative functionalization of benzoic acids with readily available halogen sources CuX (X = I, Br, Cl), and easy preparation of benzonitriles from decarboxylative cyanation of aryl carboxylic acids with nontoxic and low-cost K4Fe(CN)6 under an oxygen atmosphere for the first time.
- Fu, Zhengjiang,Li, Zhaojie,Song, Yuanyuan,Yang, Ruchun,Liu, Yanzhu,Cai, Hu
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p. 2794 - 2803
(2016/04/26)
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- Palladium-catalyzed reaction of aryl iodides with ortho-bromoanilines and norbornene/norbornadiene: Unexpected formation of dibenzoazepine derivatives
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Expecting the unexpected: The title reaction leads to satisfactory yields of dihydrodibenzoazepines 1-a from norbornene. The dibenzoazepines 2 can also be accessed from compounds of type 1-b when norbornadiene is used as a reactant. Theoretical studies show that the reaction represents a chelation-driven deviation from the usual selectivity observed in the presence of ortho-substituents on the aryl iodide.
- Della Ca', Nicola,Maestri, Giovanni,Malacria, Max,Derat, Etienne,Catellani, Marta
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supporting information; experimental part
p. 12257 - 12261
(2012/01/19)
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- COMPOUNDS
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The present invention relates to novel oxadiazole derivatives having pharmacological activity, processes for their preparation, pharmaceutical compositions containing them and their use in the treatment of various disorders.
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Page/Page column 25
(2010/03/02)
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- Design, synthesis, and fungicidal activity of novel analogues of pyrrolnitrin
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A series of novel analogues of pyrrolnitrin containing a thiophene moiety were designed and synthesized by a facile method, and their structures were characterized by 1H nuclear magnetic resonance (NMR) and high-resolution mass spectrometry. The isomers IV-h and V-h were isolated, and their structures were identified by 2D NMR, including heteronuclear multiple-quantum coherence (HMQC), heteronuclear multiple-bond correlation (HMBC), and nuclear Overhauser effect spectrometry (NOESY) spectra. Their fungicidal activities against five fungi were evaluated, and the results indicated that some of the title compounds showed excellent fungicidal activities in vitro against Alternaria solani, Gibberella zeae, Physalospora piricola, Fusarium omysporum, and Cercospora arachidicola at the dosage of 50 μg mL-1. Some compounds shown moderate activity at low dosage. Compound V-h could be considered as a leading structure for further design of agricultural fungicides.
- Wang, Ming-Zhong,Xu, Han,Feng, Qi,Wang, L.I.-Zhong,Wang, S.U.-Hua,Li, Zheng-Ming
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experimental part
p. 7912 - 7918
(2010/09/03)
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- COMPOUNDS
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The present invention relates to novel oxadiazole derivatives having pharmacological activity, processes for their preparation, pharmaceutical compositions containing them and their use in the treatment of various disorders.
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Page/Page column 53-54
(2010/01/12)
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- In search of simplicity and flexibility: A rational access to twelve fluoroindolecarboxylic acids
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All twelve indolecarboxylic acids 1-12 carrying both a fluorine substituent and a carboxy group at the benzo ring have been prepared either directly from the corresponding fluoroindoles 13-16 or from the chlorinated derivatives 22, 23 and 25 by hydrogen/metal permutation ("metalation"), or from the bromo- or iodofluoroindoles 17-20 and 26, 27, 29 and 30 by halogen/metal permutation, the organometallic intermediate being each time trapped with carbon dioxide. In most, though not all cases, the nitrogen atom in the five-membered ring had to be protected by a trialkylsilyl group. Some of the bromo- or iodofluoroindoles (26 and 27) were successfully subjected to a basicity gradient-driven selective migration of the heavy halogen. An unexpected finding on the way to the target compounds were the rigorously site-selective metalation of the 5-fluoro-N-(trialkylsilyl)indole (14b; exclusive deprotonation of the 4-position). The fluoroindoles 13-16, although previously known, were accessed more conveniently from suitably substituted nitrobenzenes using the Bartoli or the Leimgruber-Batcho method. A new and very attractive indole synthesis was elaborated consisting of the ortho-lithiation of an N-acyl-protected aniline followed by ortho-formylation, Wittig chloromethylenation and base-catalyzed cyclization accompanied by dehydrochlorination. These five consecutive steps can be contracted to a convenient one-pot protocol. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
- Schlosser, Manfred,Ginanneschi, Assunta,Leroux, Frederic
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p. 2956 - 2969
(2007/10/03)
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- High affinity central benzodiazepine receptor ligands. Part 3: Insights into the pharmacophore and pattern recognition study of intrinsic activities of pyrazolo[4,3-c]quinolin-3-ones
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Novel 2-phenyl-2,5-dihydropyrazolo[4,3-c]quinolin-3-(3H)-ones (PQs) endowed with high affinity for central benzodiazepine receptor (BzR) were synthesized. In particular, 9-fluoro-2-(2-fluorophenyl)-2,5-dihydro-3H- pyrazolo[4,3-c]quinolin-3-one (22) showed binding affinity in the subnanomolar concentration range and proved to be in vitro a potent antagonist. This finding allowed the nature of the hydrogen bonding receptor site H 2 to be established, as located between the N-1 nitrogen of the PQ nucleus and the ortho position of the N-2-aryl group. [35S]tert- Butylbicyclophosphorothionate ([35S]TBPS) binding assays and electrophysiological measurements of the effects on GABA-evoked Cl- currents at recombinant human α1β2γ 2L GABAA receptors, expressed in Xenopus laevis oocytes, were used to assess the intrinsic activities of a large series of PQs. With the aim of extracting discriminant information and distinguishing BzR ligands with different profiles of efficacy, 51 PQ derivatives, including full and partial agonists, antagonists, and inverse agonists, were analyzed in a multidimensional chemical descriptor space, defined by the lipophilicity parameter CLOG P and 3-D molecular WHIM descriptors, by means of principal component analysis, k-nearest neighbors (k-NN) method, and linear discriminant analysis (LDA). The classification methods were applied to subsets of pairs of efficacy classes, and lipophilicity and 3-D size descriptors were detected as the discriminant variables by a stepwise linear discriminant analysis. LDA proved to be superior to k-NN, especially in classifying PQ ligands (60-84% of success in prediction ability) into categories of efficacies which were contiguous and quite overlapped in the hyperspace of variables.
- Carotti, Andrea,Altomare, Cosimo,Savini, Luisa,Chiasserini, Luisa,Pellerano, Cesare,Mascia, Maria P.,Maciocco, Elisabetta,Busonero, Fabio,Mameli, Manuel,Biggio, Giovanni,Sanna, Enrico
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p. 5259 - 5272
(2007/10/03)
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- Hydroxylamine derivative of 5-nitro-8-hydroxy quinoline
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Novel hydroxylamino derivatives of the formula wherein Ar is selected from the group consisting of mono- and polycyclic aromatics and hetero-aromatics, both optionally substituted with at least one member of the group consisting of --OH, halogen, --NO2, --CN, STR1 --R7, --OR8, STR2 --SO2 R12, --SO3 R13, --COOR14, aryl of 6 to 14 carbon atoms, --OR16, --CH2 --CN and --CH2 SO2 --R15, R1, R2, R3, R4, R5 and R6 are individually selected from the group consisting of hydrogen and alkyl of 1 to 8 carbon atoms, R7 and R8 are optionally unsaturated alkyl of 1 to 8 carbon atoms optionally substituted with at least one member of the group consisting of halogen and cyano, R9, R10, R11, R12 and R13 are alkyl of 1 to 8 carbon atoms, Z is selected from the group consisting of hydrogen, optionally unsaturated alkyl of 1 to 8 carbon atoms and acyl of an organic carboxylic acid of 2 to 18 carbon atoms, R14 is selected from the group consisting of hydrogen and alkyl of 1 to 8 carbon atoms, R15 is selected from the group consisting of alkyl of 1 to 8 carbon atoms and aryl of 6 to 14 carbon atoms optionally substituted with an alkyl of 1 to 8 carbon atoms, R16 is aryl of 6 to 14 carbon atoms optionally substituted with a member of the group consisting of alkyl of 1 to 8 carbon atoms, halogen and --NO2, the substituents of Ar being able to form rings containing at least one heteroatom selected from the group consisting of oxygen, nitrogen and sulfur and their non-toxic agriculturally acceptable acid addition salts with the proviso Ar is not phenyl nor phenyl with one methyl in the 2,3 or 4 position, a nitro in the 2- or 4-position, a chlorine in the 3- or 4-position, a bromine in the 4-position or a --CF3 in the 4-position nor 2,4-dinitrophenyl nor 2-nitro-4-trifluoromethylphenyl nor 2,6-dinitrophenyl nor 2,4,6-trinitrophenyl nor 2,4-dinitro-6-trifluoromethylphenyl useful for increasing vegetation growth and increasing crop yields and their preparation.
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