cas 700-38-9, 5-Methyl-2-nitrophenol | Articles data

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3-(Ethoxycarbonyl)-1-(5-methyl-5-(nitrosooxy)hexyl)pyridin-1-ium cation: A green alternative to tert-butyl nitrite for synthesis of nitro-group-containing arenes and drugs at room temperature
Due to their remarkable properties, task-specific ionic liquids have turned out to be progressively popular over the last few years in the field of green organic synthesis. Herein, for the first time, we report that a new task-specific nitrite-based ionic liquid such as 3-(ethoxycarbonyl)-1-(5-methyl-5-(nitrosooxy)hexyl)pyridin-1-ium bis(trifluoromethanesulfonyl)imides (TS-N-IL) derived from biodegradable ethyl nicotinate indeed acted as an efficient and eco-friendly reagent for the synthesis of highly valuable nitroaromatic compounds and drugs including nitroxynil, tolcapone, niclofolan, flutamide, niclosamide and nitrazepam. The bridging of an ionic liquid with nitrite group not only increases the yield and rate of direct C[sbnd]N bond formation reaction but also allows easy product separation and recyclability of a byproduct. Nonvolatile nature, easy synthesis, merely stoichiometric need and mildness are a portion of the extra focal points of TS-N-IL while contrasted with tert-butyl nitrite an outstanding and highly-flammable reagent utilized largely in organic synthesis.
Chaudhary, Renu,Natarajan, Palani,Rani, Neetu,Sakshi,Venugopalan, Paloth
supporting information

(2019/12/30)

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)

3-Hydroxyl-4-nitrobenzoic acid and preparation method thereof
The invention aims to provide 3-hydroxyl-4-nitrobenzoic acid and a preparation method thereof. The preparation method includes: subjecting low-price and easily obtainable m-cresol as a raw material to nitration and then oxidation; with H2O2 serving as an oxidant, oxidizing a methyl group into a carboxyl group so as to obtain 3-hydroxyl-4-nitrobenzoic acid. The method has the advantages of low material cost, operation simplicity, low byproduct output, high yield and mild reaction environmental conditions and is suitable for large-scale industrial production.
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Paragraph 0029; 0030

(2017/01/23)

Regioselective nitration of phenols and phenyl ethers using aluminium nitrate on silica as a nitrating system
Silica supported aluminum nitrate (Al(NO3)3·9H2O) was found to be an excellent reagent for the nitration of phenols and phenyl ethers. This procedure works efficiently on most of the examples at room temperature yielding nitro derivatives in fair to good yields with high regioselectivity. The present methodology evidenced a considerable enhancement in the reaction rate along with high o-selectivity, excellent yields, ease of handling and the simplicity in work up.
Patil, Mahadeo R.,Mohite, Pravinkumar H.,Shisodia, Suresh,Keri, Rangappa S.
p. 129 - 135
(2015/06/23)

N-methyl-2-chloropyridinium iodide/NaNO2/Wet SiO2: Neutral reagent system for the nitration of activated aromatic compounds under very mild conditions
Mononitration of activated aromatic compounds using N-methyl-2-chloro-pyridinium iodide (Mukaiyama reagent)/NaNO2/wet SiO2 reagent system under neutral, very mild and environmentally safer reaction condition has been developed. Various structurally diverse aromatic rings are subjected in this condition and the corresponding nitro-aromatic compounds are prepared in moderately high yields.
Azadi, Roya,Nazari-Far, Zahra
p. 136 - 140
(2015/06/22)

Cyclodextrin-based artificial oxidases with high rate accelerations and selectivity
Three cyclodextrin derivatives with one to four 2-O-formylmethyl groups attached to the secondary rim were prepared and investigated as catalysts for the oxidation of aminophenols in buffered dilute hydrogen peroxide. The derivatives were found to be Michaelis-Menten catalysts and to give rate accelerations of up to 20,000 for the oxidation of 2-aminophenol to 2-amino-phenoxazin-3-one, and 12,000 for the oxidation of 2-amino-p-cresol to 2-nitro-p-cresol. While a range of differently substituted substrates was oxidized the success of the reaction was highly dependent on the substituent pattern. The ability of one of the new artificial enzymes to oxidize selectively one aminophenol from a mixture of two was investigated giving substrate selectivities of up to 16:1.
Zhou, You,Lindb?ck, Emil,Pedersen, Christian M.,Bols, Mikael
p. 2304 - 2307
(2014/04/17)

Vanadium pentoxide as a catalyst for regioselective nitration of organic compounds under conventional and nonconventional conditions
Vanadium pentoxide is used as an efficient catalyst for regioselective nitration of aromatic compounds under conventional and nonconventional conditions such as ultrasonically assisted (USAR) and microwave-assisted reactions (MWAR). The reactions underwent smoothly and afforded good yields of products with high regioselectivity. Observed longer reaction times (about 8 h) in V2O5 catalyzed reactions reduced to (0.5/30 min) under sonication and (90 s) in the case of MWAR. When ortho position is blocked, para derivatives are obtained as end products while ortho nitro products are obtained when para position is blocked.
Venkatesham,Reddy, K. Rajendar,Rajanna,Veerasomaiah
p. 921 - 926
(2014/04/03)

Ultrasonic and microwave-assisted synthesis of β-nitro styrenes and nitro phenols with tertiary butyl nitrite under acid-free conditions
Tertiary butyl nitrite (TBN) is an acid-free and safe nitrating agent that provides preferentially β-nitrostyrenes with cinnamic acids and corresponding nitro derivatives with phenols in good yields under classical conditions. However, ultrasonic and microwave-assisted reactions reduced the reaction times substantially and enhanced the yields from good to excellent. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file.
Kumar, M. Satish,Rajanna,Reddy, K. Rajendar,Venkateswarlu,Venkanna
supporting information
p. 2672 - 2677
(2013/07/26)

A tandem reduction-oxidation protocol for the conversion of 1-keto-1,2,3,4-tetrahydrocarbazoles to carbazoles via tosylhydrazones through microwave assistance: Efficient synthesis of glycozoline, clausenalene, glycozolicine, and deoxycarbazomycin B and the total synthesis of murrayafoline A
A novel and efficient methodology for the synthesis of carbazoles from 1-keto-1,2,3,4-tetrahydrocarbazoles via the corresponding tosylsulfonhydrazones by a one-pot tandem reduction-oxidation protocol using a combination of NaBH4 and Pd-C on MgSO4·7H2O, a solid support, under microwave is developed. The reaction is successfully extended toward the synthesis of several naturally occurring carbazole alkaloids, namely 3-methylcarbazole, glycozoline, clausenalene, glycozolicine, murrayafoline A, and deoxycarbazomycin B, a carbazole derivative that is known to have a promising antimicrobial activity.
Chakraborty, Suchandra,Chattopadhyay, Gautam,Saha, Chandan
p. 91 - 98
(2013/04/10)

Cellulose-supported Ni(NO3)2.6H2O/2,4,6- trichloro-1,3,5-triazine (TCT) as a mild, selective, and biodegradable system for nitration of phenols
Nitration of certain phenols and naphthols in the presence of biodegradable cellulose-supported Ni(NO3)2.6H2O/2,4,6- trichloro-1,3,5-triazine was carried out in acetonitrile at room temperature. Ortho nitrated phenols were obtained regioselectively within a short reaction time with good yields. The reaction condition was mild, and the employed cellulose could be recovered several times for further use. Copyright
Nemati, Firouzeh,Kiani, Hossein,Hayeniaz, Yaser Saeidi
experimental part
p. 2985 - 2992
(2011/08/22)

Non-steroidal dissociated glucocorticoid agonists: Indoles as A-ring mimetics and function-regulating pharmacophores
We report a SAR of non-steroidal glucocorticoid mimetics that utilize indoles as A-ring mimetics. Detailed SAR is discussed with a focus on improving PR and MR selectivity, GR agonism, and in vitro dissociation profile. SAR analysis led to compound (R)-33 which showed high PR and MR selectivity, potent agonist activity, and reduced transactivation activity in the MMTV and aromatase assays. The compound is equipotent to prednisolone in the LPS-TNF model of inflammation. In mouse CIA, at 30 mg/kg compound (R)-33 inhibited disease progression with an efficacy similar to the 3 mg/kg dose of prednisolone.
Betageri, Raj,Gilmore, Thomas,Kuzmich, Daniel,Kirrane, Thomas M.,Bentzien, J?rg,Wiedenmayer, Dieter,Bekkali, Younes,Regan, John,Berry, Angela,Latli, Bachir,Kukulka, Alison J.,Fadra, Tazmeen N.,Nelson, Richard M.,Goldrick, Susan,Zuvela-Jelaska, Ljiljana,Souza, Don,Pelletier, Josephine,Dinallo, Roger,Panzenbeck, Mark,Torcellini, Carol,Lee, Heewon,Pack, Edward,Harcken, Christian,Nabozny, Gerald,Thomson, David S.
scheme or table
p. 6842 - 6851
(2011/12/22)

Amino-acetone-bridged cyclodextrins - Artificial alcohol oxidases
A new series of α-and β-cyclodextrin derivatives containing a substituted amino-acetone bridge attached to the 6A and 6D positions of the cyclodextrin are reported. The synthesis starts from the known α-or β-cyclodextrin A,D-diols, which were either oxidized to α-or β-cyclodextrin A,D-dicarbaldehydes and then coupled with 1,3-diamino-2-propanol by a reductive amination reaction and further modified to give the final 6A,6D-diamino-6A,6 D-dideoxy-N,N'-(2-oxopropa-1,3-dienyl)-N,N'-acetyl-α-or-β- cyclodextrin or the cyclodextrindiol was substituted with azide then reduced and after a few alkylation steps the final 6A,6D-dideoxy-N, N'-(2-oxopropa-1,3-dienyl)-6A,6D-(N,N,N'N'- tetramethyldiammonio)-α-cyclodextrin dibromide was obtained. The new compounds display very good enzymatic catalytic properties in the oxidation of benzyl alcohols with a rate increase of up to 18500 but only appreciable catalysis for aniline oxidations. Thus, unlike previously studied cyclodextrin ketones, these new amino-acetone-bridged cyclodextrins have high substrate selectivity and also exhibit stereoselectivity in the oxidation of different enantiomers.
Marinescu, Lavinia G.,Doyagueez, Elisa G.,Petrillo, Marta,Fernandez-Mayoralas, Alfonso,Bols, Mikael
scheme or table
p. 157 - 167
(2010/03/26)

Zn(NO3)2·6H2O/2,4,6-trichloro-1,3,5-triazine (TCT) a mild and selective system for nitration of phenols
Certain phenols and naphthols were nitrated regioselectively with Zn(NO3)2·6H2O/TCT in acetonitrile as solvent at room temperature and short reaction time in good yields. The reaction condition was mild. TCT is a cheap and commercially available reagent. It performed as an acid catalyst in this transformation.
Nemati, Firouzeh,Kiani, Hossein
experimental part
p. 403 - 406
(2010/12/24)

Mild and selective nitration of phenols by zeofen
Certain phenols and naphthols were nitrated regioselectively with zeofen in dichloromethane as solvent at room temperature and in a short reaction time to give good yields. Copyright Taylor & Francis Group, LLC.
Bigdeli, Mohammad A.,Heravi, Majid M.,Nemati, Firouzeh
p. 2225 - 2230
(2008/02/07)

Highly efficient nitration of phenolic compounds by zirconyl nitrate
Zirconyl nitrate was found to be an excellent reagent in the nitration of phenol and substituted phenols to give nitrated phenols. This procedure works efficiently on most of the examples at room temperature yielding nitro derivatives in fair to good yields with high regioselectivity.
Selvam, J. Jon Paul,Suresh,Rajesh,Reddy, S. Ravinder,Venkateswarlu
p. 2507 - 2509
(2007/10/03)

Gas-phase reaction of hydroxyl radicals with m-, o- and p-cresol
The gas-phase reaction of oxygenated aromatic compounds m-cresol,o-cresol. and p-cresol with hydroxyl radicals has been studied by GC-MS. Experiments have been performed in a large-volume photoreactor (8000 L) at 294 ± 2 K and atmospheric pressure. The relative kinetic method was used to determine the rate constants for these reactions, with 1,3,5-trimethylbenzene as a reference compound. The rate constants obtained are kOH(m-cresol) = (5.88 ± 0.92) × 10-11 cm3 molecule-1 s-1, kOH(o-cresol) = (4.32 ± 0.52) × 10 -11 cm3 molecule-1 s-1, and k OH(p-cresol) = (4.96 ± 0.75) × 10-11 cm 3 molecule-1 s-1. The degradation products observed and their respective molar yields were methyl-1,4-benzoquinone 12.4 ± 1.2%, 5-methyl-2-nitrophenol 1.5 ± 0.3%, and 3-methyl-2-nitrophenol 1.4 ± 0.3% from m-cresol, methyl-1,4-benzoquinone 5.6 ± 0.9%, and 6-methyl-2-nitrophenol 4.7 ± 0.8% from o-cresol. and 4-methyl-2-nitrophenol 17.2 ± 2.5% from p-cresol. This kinetic and product data are compared with the literature, and the reaction mechanisms are discussed. Our results are in accordance with the previous studies (Atkinson, J Phys Chem Ref Data 1989, Monograph (1), 1-246; Atkinson and Aschmann. Int J Chem Kinet 1990, 22, 59-67; Atkinson et al., Environ Sci Technol 1992, 26, 1397-1403; Atkinson et al., J Phys Chem 1978, 82, 2759-2805; Olariu et al., Atoms Environ 2002, 36, 3685-3697; Semadeni et al., Int J Chem Kinet 1995, 27, 287-304) and confirm the methyl-1,4-benzoquinone yields determined by a different experimental technique (long-path Fourier transform infrared FT-IR (Olariu et al., 2002)).
Coeur-Tourneur, Cecile,Henry, Francoise,Janquin, Marie-Andree,Brutier, Laurent
p. 553 - 562
(2008/02/10)

p-Toluenesulfonic acid catalyzed regiospecific nitration of phenols with metal nitrates
Highly regiospecific mononitration of phenols and substituted phenols is accomplished employing a metal nitrate and a catalytic amount of p-toluenesulfonic acid in acetone. An exclusive ortho-selectivity was observed with excellent yields. A variety of metal nitrates were used to obtain o-nitrophenols exclusively in good to excellent yields. The use of p-toluenesulfonic acid is key for the selectivity observed.
Anuradha,Srinivas,Aparna,Rao, J. Madhusudana
p. 4933 - 4935
(2007/10/03)

Nitration of phenolic compounds by metal-modified montmorillonite KSF
The nitration of phenolic compounds with 60% nitric acid (1.2 equiv) has been carried out in the presence of metal-modified montmorillonite KSF, prepared from different metals (V, Mo, W; Sc, La, Yb, Eu, In, Bi, Ti, Zr, Hf) and KSF or nitric acid treated HKSF, as catalysts. These catalysts showed good stabilities and high catalytic activities in nitration process. In addition, these catalysts can be recovered easily and reused for many times in nitration. This process is an eco-safer and environment-benign way for clean synthesis of nitrated phenolic compounds.
Yin, Wan-Po,Shi, Min
p. 10861 - 10867
(2007/10/03)

Nitrophenol derivatives oxidized by cerium(IV) ammonium nitrate (CAN) and their cytotoxicity
Oxidation of a series of phenols with cerium(IV) ammonium nitrate (CAN) in acetonitrile undermild conditions yields the mixture of corresponding nitrophenols. In the cases of methylphenols and hydroxy-carboxylic acids, the steric effect may reduce the nitration reaction. Compounds 3 a and 4b showed selective activities to Hep 3B and Hep G2 cancer cell lines, respectively. Compound 2c showed selective activities to Hep G2 and MDA-MB-231 cancer cell lines. Further more, com pound 10b showed selective activities to Hep G2, Hep 3B, MCF-7 and MDA-MB-231 cancer cell lines.
Pan, Wen-Bin,Wei, Li-Mei,Wei, Li-Lan,Wu, Chin-Chung,Chang, Fang-Rong,Wu, Yang-Chang
p. 581 - 588
(2007/10/03)

Supramolecular oxidation of anilines using hydrogen peroxide as stoichiometric oxidant
6A,6D-Di-O-(propan-2-on-1,3-diyl) α-cyclodextrin-6A,6D-dicarboxylate (2α) and 6A,6D-di-O-(propan-2-on-1,3-diyl) β-cyclodextrin-6A,6D-dicarboxylate (2β) were found to catalyze the oxidation of aromatic amines in the presence of hydrogen peroxide. The products were the corresponding nitro compounds or in some cases azo-, azoxy-, or other dimerization products. The catalysis was found to follow enzyme kinetics giving a rate increase (kcat/kuncat) of up to 1100 in the best case. Copyright
Marinescu, Lavinia,Molbach, Merete,Rousseau, Cyril,Bols, Mikael
p. 17578 - 17579
(2007/10/03)

Highly efficient catalytic nitration of phenolic compounds by nitric acid with a recoverable and reusable Zr or Hf oxychloride complex and KSF
Phenolic compounds can be nitrated with 60% nitric acid (1.2 equiv.) in the presence of catalytic amounts of a Zr or Hf oxychloride complex and montmorillonite KSF to give the corresponding nitrated products in good yields in a heterogeneous catalytic system. The co-catalyst and montmorillon ite can be easily recovered and reused in the next batch of nitration. This is a practical process for the nitration of phenolic compounds in a clean way. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Shi, Min,Cui, Shi-Cong,Yin, Wan-Po
p. 2379 - 2384
(2007/10/03)

Highly efficient nitration of phenolic compounds in solid phase or solution using Bi(NO3)3·5H2O as nitrating reagent
Bi(NO3)3·5H2O was used as an efficient nitrating reagent in the nitration of phenolic compounds to give nitrated phenols in good to high yields. The nitration reaction proceeded smoothly by grinding 1 equiv of phenol, 2-methylphenol, 4-methylphenol, or 4-chlorophenol and Bi(NO3)3· 5H2O, and the nitration of other phenolic compounds could be performed in acetone at ambient temperature (22-30 °C).
Sun, Hong-Bin,Hua, Ruimao,Yin, Yingwu
p. 9071 - 9073
(2007/10/03)

A New Method for Nitration of Phenolic Compounds
Phenolic compounds can be nitrated by 65% nitric acid in the presence of catalytic amounts of montmorillonite KSF and bismuth(III) nitrate to give the corresponding nitrated products in good yields in a heterogeneous phase. The co-catalyst of KSF and Bi(NO3)3 can be easily recovered and reused in the next batch of nitration.
Shi, Min,Cui, Shi-Cong
p. 1197 - 1202
(2007/10/03)

Regioselectivity of the nitration of phenol by acetyl nitrate adsorbed on silica gel
The reaction of phenol with acetyl nitrate in chloroform gives nitrophenol with an ortho/para ratio of 1.8. This ratio increase to 13.3 when the reaction was carried out with acetyl nitrate pre-adsorbed on dry silica gel. Silica may be acting as a template to bring phenol close to acetyl nitrate by hydrogen bonds forming a ternary complex, which undergoes a six- center rearrangement to o-nitrophenol. The formation of this ternary complex is evaluated by ab initio molecular orbital calculation.
Augusto,Rodrigues,De Oliveira Filho, Antonio Pedro,Moran, Paulo J. S.,Custodio, Rogerio
p. 6733 - 6738
(2007/10/03)

Synthesis of p-Nitrophenols
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Suboch,Belyaev
p. 288 - 288
(2007/10/03)

Mild and Selective Nitration by "Claycop"
A one-pot nitration of aromatic compounds by "claycop", a reagent consisting of an acidic montmorillonite clay impregnated with anhydrous cupric nitrate, is reported.Simply by varying the conditions, it is possible to drive the reaction at will toward either mono- or polynitration.Both the yields and selectivities are superior to those obtained under homogeneous reaction conditions.
Gigante, Barbara,Prazeres, Angela O.,Marcelo-Curto, Maria J.,Cornelis, Andre,Laszlo, Pierre
p. 3445 - 3447
(2007/10/02)

Cerium(IV) induced oxidative coupling of simple phenols in the presence and absence of hydrogen peroxide: A comparative study of product distribution
The reaction of cerium(IV) ammonium nitrate with simple phenols (2-, 3- and 4-methylphenols) has been examined in the presence and absence of hydrogen peroxide.It has been observed that though the oxophilicity of cerium(IV) can be controlled by addition of hydrogen peroxide in the reaction medium, there is also a difference in the nature of products formed.The reaction can be used to obtain new terphenyls (3a, 3b and 3e), biphenyls (2a, and 2e), 2-hydroxy-1,9-dimethyl-7-nitro-dibenzyl-p-dioxin (4) and 3,7-dimethyl-1,9-dinitrodibenzofuran (5) in acceptable net yields.
Chakrabarty, Kakoli,Chawla, H. Mohindra,Suresh, Valiya Veettil
p. 266 - 274
(2007/10/02)

Reaction of cerium(IV) ammonium nitrate with simple phenols in a silica gel matrix
The oxophilicity of cerium(IV) ammonium nitrate is moderated by the addition of hydrogen peroxide.The reaction with simple phenols becomes regioselective when carried out in a silica gel matrix.The methodology has been employed for the synthesis of new functionalized terphenyls and biphenyls.
Chakrabarty, K,Chawla, H M,Suresh, V V
p. 464 - 466
(2007/10/02)

The Rearrangement of Aromatic Nitro Compounds. Part 2. The Rearrangement os Substituted Nitrophenols in Trifluoromethanesulphonic Acid
o-Nitrophenols with an additional substituent (Y = NO2, Cl, or Me) in the 3-position rearrange in trifluoromethanesulphonic acid at 100 deg C to give mainly the product with the nitro group in the opposite ortho position; no more than 1-4percent of other products are formed.The reactions give first-order kinetics, are acid-catalysed and (at least when Y = NO2) are intramolecular.The rate of rearrangement varies with the 3-substituent in the order Me > Cl > NO2.The results are discussed in terms of a rate-determining migration of the nitro group in the Wheland intermediate formed by protonation at the 2-position.A much slower rearrangement occurs with 3,4-dinitrophenol under the same conditions to give a small yield of 2,5-dinitrophenol accompanied by decomposition of the substrate.
Bullen, John V.,Ridd, John H.
p. 1675 - 1679
(2007/10/02)

A THEORETICAL STUDY ON THE TWO-PHASE NITRATION OF PHENOLS
The two-phase nitration of phenols is an example of nitrous acid catalysed nitration.Semi-empirical molecular orbital calculations were undertaken on the ground state, radical cation and the phenoxy radical.Unpaired electron spin density calculations can succesfully predict isomer ratios for 3-substitued phenols.Catalysis by NO+ suggests a radical recombination mechanism based on initial electron transfer to form te radical cation followed by proton loss to generate the phenoxy radical.
Thompson, Malcolm J.,Zeegers, Petrus J.
p. 191 - 202
(2007/10/02)

MONONITRATION DE PHENOLS PAR DES NITRATES METALLIQUES
A new and practical route to mononitrphenol in high yields is described using commercially aviable hydrated metallic nitrates.According to the metallic nitrate used, this reaction can yield regiospecifically the ortho-nitrophenol or regioselectively the para-nitrophenol.This method is successfully applied to some phenolic derivatives, in particular to the preparation of 2-nitroestrone.Sodium nitrate with ferric chloride or with titane tetrachloride allows mononitration of phenol.
Poirier, Jean-Marie,Vottero, Catherine
p. 1415 - 1422
(2007/10/02)

STUDIES ON THE TWO-PHASE NITRATION OF SELECTED PHENOLS
The two phase nitration of several phenols by aqueous acid, sodium nitrate and diethyl ether, yielded as well as the expected nitro-phenols, a benzoquinone.A variable induction period was observed which could be significantly reduced by added sodium nitrite.
Thompson, Malcolm J.,Zeegers, Petrus J.
p. 2471 - 2474
(2007/10/02)

NITRATION OF PHENOLS BY CLAY-SUPPORTED FERRIC NITRATE
"Clayfen", a reactive form of ferric nitrate stabilized by adsorption unto an acidic K 10 clay, is an efficient and selective nitrating agent of phenols, under very mild conditions.It leads specifically to mononitration, with high regioselectivities.These characteristics, coupled with its low cost, ease of preparation and the simplicity of experimental procedures, make "clayfen" an attractive nitrating reagent.
Cornelis, A.,Laszlo, P.,Pennetreau, P.
p. 961 - 972
(2007/10/02)

255. Construction of Highly Substituted Nitroaromatic Systems by Cyclocondensation. Part II. Conversion of 4-Nitr-3-oxobutyrate to 3-Nitrosalicylates
The base-catalyzed reaction of 4-nitro-3-oxobutyrate (6) with acetylacetone (8), formylacetone (13), formylcyclohexanone (31), 2,4-dioxopentanoates 39 and 40, and 2,4,6-heptanetrione (2) affords substituted 3-nitrosalicylates, products of a double aldol condensation.With unsymmetrical dicarbonyl compounds both regioisomers are formed.High selectivity was found in the case of β-keto-aldehydes 13 and 31 with preferred addition of the NO2-substituted carbon to the aldehyde carbonyl.The major products of these cyclocondensations, which are isolated in yields ranging from 20 percent to 80 percent, are all new compounds.Less successful are the conversions with β-alkoxy- and β-chloro-vinyl ketones (23, 25, and 26), and with alkinone 24, where the condensation products are formed in very low yield.
Duthaler, Rudolf O.
p. 2543 - 2563
(2007/10/02)

SELECTIVE NITRATION OF PHENOLS CATALYZED BY LANTHANUM (III) NITRATE
Phenols are easily mononitrated at room temperature by NaNO3 in a two-phase system (water - ether) in presence of HCl and a catalytic amount of La(NO3)3.The experimental conditions leave completely unaltered many other aromatic systems.
Ouertani, M.,Girard, P.,Kagan, H.B.
p. 4315 - 4318
(2007/10/02)

Photochemical Nucleophilic Substitution Reactions of Methyl Substituted Derivatives of p- and o-Nitroanisole
Photosubstitution reactions of several methyl substituted derivatives of p- and o-nitroanisole with hydroxide ion were investigated.The methyl substituent seemed to show an uncertain (probably electronic) effect in addition to the steric effect for the replacement of both the methoxy and the nitro groups.Mainly, the replacement reaction of the nitro group is discussed.
Sawaura, Masaki,Mukai, Toshio
p. 3213 - 3214
(2007/10/02)

Electrophilic aromatic substitution. Part 24. The nitration of isopropylbenzene, 2- and 4-isopropyltoluene, 1-chloro-4-isopropylbenzene, 4-isopropylanisole, and 2-bromotoluene: Nitrodeisopropylation
The kinetics and products of nitration in aqueous sulphuric acid of the title compounds have been studied. 4-Isopropyl-phenol and -anisole are nitrated at or near the encounter rate. In 65-79% H2SO4 2-isopropyltoluene suffers ca. 25% ipso-attack; the only fate of W iPri (ipso-Wheland intermediate) is nitrodeisopropylation. From 4-isopropyltoluene WiPri is also nitrodeisopropylated, but some 1,2-nitro-migration may occur. From the same compound WiMe may be captured by water, rearrange, or give 4-methylacetophenone; a mechanism is proposed for the formation of the last compound. Nitrodeisopropylation occurs without the assistance of water. With 4-isopropylanisole, demethoxylation and nitrodeisopropylation are consequences of the formation of WiPri. The results are consistent with increasing attack at C-4 with increasing acidity, loss of isopropyl without assistance from water, and decomposition of the unobserved intermediate, 4-isopropyl-4-nitrocyclohexa-2,5-dienone, by two processes. One, acid-catalysed process gives 4-nitrophenol and possibly 4-isopropyl-2-nitrophenol. The other, probably radical, process gives 4-isopropyl-2-nitrophenol. In contrast to 4-bromotoluene, 2-bromotoluene is not nitrodebrominated.
Manglik, Ajay K.,Moodie, Roy B.,Schofield, Kenneth,Tobin, Geoffrey D.,Coombes, Robert G.,Hadjigeorgiou, Panicos
p. 1606 - 1616
(2007/10/02)

2-STYRYLBENZOXAZOLE DERIVATIVES
A series of 35 derivatives of 2-styrylbenzoxazole I-XXXV with methyl, chloro, hydroxy, methoxy, dimethylamino, nitro, cyano and methoxycarbonyl substituents have been prepared by reaction of substituted 2-acetamidophenol with respective benzaldehyde derivatives.
Arient, Josef
p. 3160 - 3165
(2007/10/02)

Manufacture of para-nitro-meta-cresol from meta/para-cresol mixtures
Process for the manufacture of para-nitro-meta-cresol in high yield from directly available and inexpensive meta/para-cresol mixtures, without need heretofore for first resolving the cresol mixture to provide a separate meta-cresol reactant. The process comprises subjecting the cresol mixture to nitration, whereby para-nitro-meta-cresol is formed, and then separating the para-nitro-meta-cresol from the resulting nitration reaction mixture. In one embodiment, the cresol mixture is introduced into reaction with an aqueous acid mixture containing HNO3 and HNO2 as the only acid ingredients, under defined critical conditions of feed flow rate, temperature, acid concentrations, and reactant proportions to provide the cresol nitration reaction product mixture.
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(2008/06/13)