cas 491-11-2, 3-chloro-4-nitrophenol | Articles data

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Compound containing FXR agonist, and preparation method and application thereof
The invention belongs to the technical field of medicines, and concretely relates to a compound containing an FXR agonist, represented by general formula (I), or a pharmaceutically acceptable salt thereof, a preparation method of the compounds, a pharmaceutical composition and a pharmaceutical preparation containing the compounds, and an application of the compounds in the preparation of drugs used for treating and/or preventing FXR mediated diseases. R, R, R, R, m, n, p, q, T, L1-L2 and A ring or B ring in the formula (I) are defined in the description.
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Paragraph 0229-0232

(2020/03/25)

Method for hydrolyzing nitroaniline substances into phenol
The invention discloses a method for hydrolyzing nitroaniline substances into phenol. The method comprises the following steps: mixing the nitroaniline substances, a catalyst and inorganic base whichare used as raw materials with water used as a solvent, adding the mixture to a reactor, sealing the reactor, and heating the reactor to 100-190 DEG C for a reaction for 2-8 h; cooling an obtained reaction solution to room temperature, then, adjusting pH to 1-2, and washing and drying obtained precipitates to obtain the product, namely, nitrophenol substances. The nitrophenol substances are synthesized with the method, the utilization rate of the raw materials is high, expensive catalysts are not used, emission of three wastes is reduced, the production cost is reduced, and the product has high purity, high yield and good industrial application values.
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Paragraph 0085-0087; 0098-0101

(2019/07/04)

Kinetics and mechanism of trichloroisocyanuric acid/NaNO2-triggered nitration of aromatic compounds under acid-free and Vilsmeier-Haack conditions
Kinetics and mechanism of nitration of aromatic compounds using trichloroisocyanuric acid (TCCA)/NaNO2, TCCA-N,N-dimethyl formamide (TCCA-DMF)/NaNO2, and TCCA-N,N-dimethyl acetamide (TCCA-DMA)/NaNO2 under acid-free and Vilsmeier-Haack conditions. Reactions followed second-order kinetics with a first-order dependence on [Phenol] and [Nitrating agent] ([TCCA], [(TCCA-DMF)], or [(TCCA-DMA)] >> [NaNO2]). Reaction rates accelerated with the introduction of electron-donating groups and retarded with electron-withdrawing groups, but did not fit well into the Hammett's theory of linear free energy relationship or its modified forms like Brown-Okamoto or Yukawa-Tsuno equations. Rate data were analyzed by Charton's multiple linear regression analysis. Isokinetic temperature (β) values, obtained from Exner's theory for different protocols, are 403.7?K (TCCA-NaNO2), 365.8?K (TCCA-DMF)/NaNO2, and 358?K (TCCA-DMA)/NaNO2. These values are far above the experimental temperature range (303-323?K), indicating that the enthalpy factors are probably more important in controlling the reaction.
Bhooshan,Rajanna,Govardhan,Venkanna,Satish Kumar
p. 445 - 462
(2019/04/10)

Sodium perborate/NaNO2/KHSO4-triggered synthesis and kinetics of nitration of aromatic compounds
Sodium perborate (SPB) was used as efficient green catalyst for NaNO2/KHSO4-mediated nitration of aromatic compounds in aqueous acetonitrile medium. Synthesis of nitroaromatic compounds was achieved under both conventional and solvent-free microwave conditions. Reaction times were comparatively shorter in the microwave-assisted than conventional reaction. The reaction kinetics for nitration of phenols in aqueous bisulfate and acetonitrile medium indicated first-order dependence on [Phenol], [NaNO2], and [SPB]. Reaction rates accelerated with introduction of electron-donating groups but retarded with electron-withdrawing groups. Kinetic results did not fit well quantitatively with Hammett’s equation. Observed deviations from linearity were addressed in terms of exalted Hammett’s constants (σˉ or σeff), para resonance interaction energy (ΔΔGp) parameter, and Yukawa–Tsuno parameter (r). This term provides a measure of the extent of resonance stabilization for a reactive structure that builds up charge (positive) in its transition state. The observed negative entropy of activation (?ΔS#) suggests greater solvation and/or cyclic transition state before yielding products.
Rajanna,Muppidi, Suresh,Pasnoori, Srinivas,Saiprakash
p. 6023 - 6038
(2018/09/21)

Potassium Periodate/NaNO2/KHSO4-Mediated Nitration of Aromatic Compounds and Kinetic Study of Nitration of Phenols in Aqueous Acetonitrile
Synthesis and kinetics of potassium periodate(KIO4)/NaNO2/KHSO4)-initiated nitration of aromatic compounds have been studied in aqueous acetonitrile medium. Synthesis of nitroaromatic compounds is achieved under conventional and solvent-free microwave conditions. Reaction times in microwave-assisted reaction are comparatively less than in conventional reaction. The reaction kinetics for the nitration of phenols in aqueous bisulfate and acetonitrile medium indicated first-order dependence on [phenol], [NaNO2], and [KIO4]. An increase in [KHSO4] accelerated the rate of nitration under otherwise similar conditions. The rate of nitration increased in the solvent of high dielectric media (solvents with high dielectric constant (D)). Observed results were in accordance with Amis and Kirkwood plots [log k′ vs. (1/D) and [(D ? 1)/(2D + 1)]. These observations probably indicate the participation of anionic species and molecular or (dipolar) species in the rate-determining step. In addition, the plots of (log k′) versus volume% of organic solvent were also linear, which probably indicate the importance of both electrostatic and nonelectrostatic forces, solvent–solute interactions during nitration of phenols. Reaction rates accelerated with the introduction of electron-donating groups and retarded with electron-withdrawing groups, but results could not be quantitatively correlated with Hammett's equation and depicted deviations from linearity. These deviations could probably be attributed to cumulative effects arising inductive, resonance, and steric effects. Leffler's plot (ΔH# vs. ΔS#) was found linear indicating the compensation (cumulative) effect of both enthalpy and entropy parameters in controlling the mechanism of nitration.
Sriram, Y. Hemanth,Fatima, Touheeth,Rajanna,Kumar, M. Satish,Raju, R. Madhusudan
supporting information
p. 622 - 632
(2017/06/30)

Production method of 3-ethoxy-4-nitrophenol
The invention discloses a production method of 3-ethoxy-4-nitrophenol. The low-price m-dichlorobenzene is used instead of the high-price resorcinol as the raw material, and the methoxy is converted into the hydroxy; and a simple alkaline process is used instead of the conventional hydrogen bromide/acetic acid system to prepare the 3-ethoxy-4-nitrophenol. By using low-price m-dichlorobenzene instead of the high-price resorcinol as the raw material to prepare the 3-ethoxy-4-nitrophenol, the method has the advantages of simple synthesis steps, low pollution, environment friendliness, high product quality, high yield, low production cost and normal-pressure operation, and can implement industrial production.
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Paragraph 0036

(2017/05/26)

Tertiary Butyl Nitrite Triggered Nitration of Phenols: Solvent- and Structure-Dependent Kinetic Study
Nitration of phenols with tertiary butyl nitrite (TBN) obeyed second-order kinetics with a first-order dependence on [TBN] and [phenol] under acid-free conditions. Reaction rates were significantly altered by a change in the dielectric constant and other physical properties of solvent. The rate of nitration increased with an increase in temperature (303-323 K) in different solvent media (acetonitrile, dichloroethane, CCl4, dimethyl formamide (DMF), and toluene). The rates of nitration (log k) could not fit into either Amis or Kirkwood plots [log k' vs. (1/D) or [(D - 1)/(2D + 1)], but the trends were better explained by the basic form of multivariate linear solvent energy relationships (MLSER) suggested by the Koppel and Palm approach on the one hand and the Kamlet and Taft approach on the other hand. These observations probably substantiate that cumulative contributions of basic solvent parameters (equilibrium as well as frictional solvent effects) and solvent-solute interactions for solvation of transition state during nitration of phenols. Reaction rates accelerated with the introduction of electron-donating groups and retarded with electron-withdrawing groups. Accordingly, the reactivity of structurally different phenols was found to follow the following sequence: p-OH > p-MeO > p-Me > H > m-Me > p-Cl > p-Br > m-Cl > p-NO2 > m-OH. The results are interpreted by Hammett's theory of linear free energy relationship. The reaction constant (Hammett's ρ) is a measure of the sensitivity of the reaction toward the electronic effects of the substituent. The rho (ρ) values obtained from the present experiments are fairly large negative values (ρ CH3) versus σ? or, Es or combined Taft's relationship. However, Charton's MLRA of the log k with polar, resonance, steric, hydrophobicity, and molar refractivity showing a very good linear relationship was obtained. It is of interest to note that when log kexp values are correlated with log kcal a perfect linearity is obtained with a correlation coefficient of unity, indicating the consonance between experimental and calculated rate constants in the present work.
Kumar, M. Satish,Rajanna,Venkateswarlu,Rao, K. Lakshman
supporting information
p. 171 - 196
(2016/04/09)

A practical approach for regioselective mono-nitration of phenols under mild conditions
Cu(NO3)2.3H2O was demonstrated to be an efficient, regioselective and inexpensive nitrating reagent for the synthesis of mono-nitro substituted phenolic compounds. 12 examples of different phenols were examined. Good yields (67-90%) have been achieved. ARKAT-USA, Inc.
Chen, Ling-Yan,Liu, Tao,Zhou, Xiaokun,Sun, Zhihua
p. 64 - 71
(2014/07/22)

A probable hydrogen-bonded meisenheimer complex: An unusually high S NAr reactivity of nitroaniline derivatives with hydroxide ion in aqueous media
Observations show that nitroanilines exhibit an unusually high S NAr reactivity with OH- in aqueous media in reactions that produce nitrophenols. SNAr reaction of 4-nitroaniline (2a) in aqueous NaOH for 16 h yields 4-nitrophenol (4a) quantitatively, whereas a similar reaction of 4-nitrochlorobenzene (1a) gave 4a in 2% yield together with recovered 1a in 97%, suggesting that the leaving ability of the NH2 group far surpasses that of Cl under these conditions. An essential feature of SNAr reactions of nitroanilines is probably that the NH2 leaving group participates in a hydrogen-bonding interaction with H 2O. Density functional theory (DFT) calculations for a set of 4-nitroaniline, OH-, and H2O suggest a possible formation of a Meisenheimer complex stabilized by hydrogen-bonding interactions and a six-membered ring structure. The results obtained here contrast with conventional SNAr reactivity profiles in which nitroanilines are nearly unreactive with nucleophiles in organic solvents.
Imoto, Mitsutaka,Matsui, Yasunori,Takeda, Motonori,Tamaki, Akihiro,Taniguchi, Hisaji,Mizuno, Kazuhiko,Ikeda, Hiroshi
experimental part
p. 6356 - 6361
(2011/10/05)

Nitration of phenolic compounds and oxidation of hydroquinones using tetrabutylammonium chromate and dichromate under aprotic conditions
In this work, we have reported a mild, efficient and selective method for the mononitration of phenolic compounds using sodium nitrite in the presence of tetrabutylammonium dichromate (TBAD) and oxidation of hydroquinones to quinones with TBAD in CH2Cl2. Using this method, high yields of nitrophenols and quinones were obtained under neutral aprotic conditions. Tetrabutylammonium chromate (TBAC) can also be used as oxidant at same conditions. Indian Academy of Sciences.
Pourali, Ali Reza,Goli, Arezou
scheme or table
p. 63 - 67
(2012/01/13)

KINASE INHIBITORS AND METHODS OF USE
The present invention provides chemical entities or compounds and pharmaceutical compositions thereof that are capable of modulating certain protein kinases such as mTor, tyrosine kinases, and/or lipid kinases such as PI3 kinase. Also provided in the present invention are methods of using these compositions to modulate activities of one or more of these kinases, especially for therapeutic applications.
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Page/Page column 81-82

(2010/04/03)

Synthesis of functionalized indole- and benzo-fused heterocyclic derivatives through anionic benzyne cyclization
The development of a new method for the regioselective synthesis of functionalized indoles and six-membered benzo-fused N-, O-, and S-heterocycles is reported. The key step involves the generation of a benzyne-tethered vinyl or aryllithium compound that undergoes a subsequent intramolecular anionic cyclization. Reaction of the organolithium intermediates with selected electrophiles allows the preparation of a wide variety of indole, tetrahydrocarbazole, dihydrofenantridine, dibenzopyran, and dibenzothiopyran derivatives. Finally, the application of this strategy to the appropriate starting materials allows the preparation of some tryptamine and serotonin analogues.
Barluenga, Jose,Fananas, Francisco J.,Sanz, Roberto,Fernandez, Yolanda
p. 2034 - 2046
(2007/10/03)

Hydroxylation of Nitroarenes with Alkyl Hydroperoxide Anions via Vicarious Nucleophilic Substitution of Hydrogen
Rhone-Poulenc Polska Ltd., ul. Grzybowska 80/82, 00-844 Warszawa, Poland Garbo- and heterocyclic nitroarenes react with anions of tert-butyl and cumyl hydroperoxides in the presence of strong bases to form substituted o- and p-nitrophenols. The reaction usually proceeds in high yields and is of practical value as a method of synthesis and manufacturing of nitrophenols. Orientation of the hydroxylation can be controlled to a substantial extent by selection of the proper conditions. Basic mechanistic features of this process were clarified.
Makosza, Mieczyslaw,Sienkiewicz, Krzysztof
p. 4199 - 4208
(2007/10/03)

Transition metal complexes in organic synthesis. Part 46: Synthesis of 5-arylmethyl-substituted tricarbonyl(1-4-η-cyclohexa-1,3-diene)iron complexes
The reaction of tricarbonyl(η5-cyclohexadienylium) iron tetrafluoroborate 3 with the methyl arylacetate 6, the dimethyl arylmalonate 12, and the di-tert-butyl arylmalonate 14 provides regio- and stereoselectively the tricarbonyliron-complexed 5
Knoelker, Hans-Joachim,Graf, Michael,Mangei, Ulrike
experimental part
p. 530 - 535
(2011/10/12)

Concerted displacement mechanism at trigonal carbon: the aminolysis of 4-aryloxy-2,6-dimethoxy-1,3,5-triazines
4-Aryloxy-1,3,5-triazines undergo bimolecular nucleophilic displacement reactions with amines and pyridines to yield the 4-substituted triazine and aryloxide ion.Rate constants in aqueous solution for the bimolecular reaction of morpholine and 4-dimethylaminopyridine with the title ethers obey the Hammett ? evaluation with Hammett ρlg values 1.65 and 0.82, respectively.Comparison of the ρlg values with the Hammett ρeq for the equilibrium constants indicates that build-up of effective charge on the departing ether oxygen in the transition structures is less than half of that for complete bond fission.Rate constants for the reaction of substituted pyridines with the 4-nitro- and 3,4-dinitro-phenyl ethers obey Broensted equations with exponents βnuc of 0.68 and 1.06, respectively.The build-up of effective charge in bond formation is greater than half of that expected for complete bond formation.Variation in βnuc and ρlg as a function of leaving group and nucleophile structure, respectively, is consistent with substantial coupling between bond forming and bond breaking.The ratio of the Leffler exponents in the pyridinolysis reactions, αnuc/αlg, is greater than unity, consistent with an imbalance between bond fission and bond formation and indicating an accumulation of negative charge in the heteroaromatic nucleus in the transition structure 29percent of that expected for adduct formation.
Shakes, Janice,Raymond, Christel,Rettura, Donatella,Williams, Andrew
p. 1553 - 1558
(2007/10/03)

Convenient strategies for the preparation of modified 2(3H)-benzothiazolethiones
4-Alkyl-2-bromoanilines and 4-alkoxy-2-chloroanilines were synthesized conveniently and submitted to cyclization reaction with potassium O-ethyl dithiocarbonate to afford 6-substituted 2(3H)-benzothiazolethiones in good yields.
Chaudhuri, Narayan C.
p. 3783 - 3790
(2007/10/03)

Stepwise versus concerted mechanisms at trigonal carbon: Transfer of the 1,3,5-triazinyl group between aryl oxide ions in aqueous solution
Displacements of 4-nitrophenolate ions from 2-(4-nitrophenoxy)-4,6-dimethoxy-1,3,5-triazine by substituted phenolate ions in aqueous solution obey a linear Br?nsted-type equation, log kArO = 0.951pKa - 10.98, over a range of pKa values greater than and less than the pKa of the leaving phenol. The absence of curvature is consistent with a mechanism involving a single transition state. This conclusion is supported by the existence of cross-correlation effects (Pxy = 0.0561) on βnuc of the pKa of the leaving group and on β1g of the pKa of the nucleophile on β1g. The value of βeq, the Br?nsted selectivity for transfer of the triazinyl function between phenolate ions, is calculated from the Br?nsted data to be 1.48. The identity reaction of 3,4-dinitrophenolate ion with the (3,4-dinitrophenoxy)triazine is calculated to have a Kreevoy-Albery τ value of 1.04, indicating that in this case changes in effective charge on entering and leaving ligands are approximately balanced.
Renfrew, A. Hunter M.,Rettura, Donatella,Taylor, John A.,Whitmore, James M. J.,Williams, Andrew
p. 5484 - 5491
(2007/10/02)

REACTION OF AROMATIC COMPOUNDS WITH NUCLEOPHILIC REAGENTS IN LIQUID AMMONIA. XIII. DIRECTION OF HYDROXYLATION OF 2-HALONITROBENZENES BY POTASSIUM HYDROXIDE
The reaction of 2-fluoronitrobenzene with potassium hydroxide and molecular oxygen in liquid ammonia at -33 deg C gave 2-nitrophenol.In contrast to 2-fluoronitrobenzene, both the halogen and hydrogen in the ortho and para positions to the nitro group are replaced in the reactions of 2-chloro- and 2-bromonitrobenzenes, KOH, and O2.In the case of 2-bromonitrobenzene, there is significant formation of a compound, formally corresponding to reductive dehalogenation (nitrobenzene and its hydroxylation product, 4-nitrophenol) and bromination of the nitrophenols formed in the position to the hydroxy group.
Malykhin, E. V.,Kolesnichenko, G. A.,Shteingarts, V. D.
p. 1149 - 1152
(2007/10/02)

Synthesis of mitomycin C analogues. 2. Introduction of a leaving group at C-1 and oxidation of the aromatic ring in 2,3,9,9a-tetrahydro-1H-pyrrolo[1,2-a]indoles
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Verboom,Lammerink,Egberink,et al.
p. 3797 - 3806
(2007/10/02)

ACID BASE REACTIONS BETWEEN ACRIDINE ORANGE AND SUBSTITUTED PHENOLS IN BENZONITRILE. PART I. THERMODYNAMICS OF ASSOCIATION AND IONIC EQUILIBRIA.
Proton transfer reactions of the five substituted phenols 3-Cl-4-nitrophenol CNP, 4-nitrophenol NP, 3-methyl-4-nitrophenol MNP, 4-Cl-3,5-dimethylphenol CMP, and 3,5-dimethylphenol DMP with acridine orange, and the formation of hydrogen bonded complexes AHA** minus of the anions A** minus of CNP, NP, and MNP with the respective phenols AH in benzonitrile solution were investigated by means of absorption spectroscopy. The formation enthalpies of the hydrogen bonded anions AHA** minus are much larger than DELTA H//1, so that DELTA H//2 is mainly determined by this association. On the other hand there is no significant difference between DELTA H//2 and DELTA H//3; thus the hydrogen bond formed between a phenol and a complexed anion AHA** minus is very weak. Substituent effects on the acidity of phenols are about twice as large in benzonitrile as in aqueous solution.
Suettinger,Strohbusch
p. 744 - 750
(2007/10/02)