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Advanced Real-Time Process Analytics for Multistep Synthesis in Continuous Flow**
In multistep continuous flow chemistry, studying complex reaction mixtures in real time is a significant challenge, but provides an opportunity to enhance reaction understanding and control. We report the integration of four complementary process analytical technology tools (NMR, UV/Vis, IR and UHPLC) in the multistep synthesis of an active pharmaceutical ingredient, mesalazine. This synthetic route exploits flow processing for nitration, high temperature hydrolysis and hydrogenation reactions, as well as three inline separations. Advanced data analysis models were developed (indirect hard modeling, deep learning and partial least squares regression), to quantify the desired products, intermediates and impurities in real time, at multiple points along the synthetic pathway. The capabilities of the system have been demonstrated by operating both steady state and dynamic experiments and represents a significant step forward in data-driven continuous flow synthesis.
Sagmeister, Peter,Lebl, René,Castillo, Ismael,Rehrl, Jakob,Kruisz, Julia,Sipek, Martin,Horn, Martin,Sacher, Stephan,Cantillo, David,Williams, Jason D.,Kappe, C. Oliver
supporting information
p. 8139 - 8148
(2021/03/01)

Method for synthesizing mesalazine
A method for synthesizing mesalazine is disclosed. The method comprises the following steps: 1) adding p-nitrophenol, p-toluenesulfonic acid, absolute ethyl alcohol and hexamethylenetetramine, stopping heating after the reaction is finished, heating to room temperature while stirring with ice water, separating out solids, filtering, washing and drying to obtain 5-nitrosalicylaldehyde; 2) adding the 5-nitrosalicylaldehyde, potassium tert-butoxide, copper salt and acetonitrile, adding tert-butyl hydroperoxide while stirring, after the reaction is finished, performing vacuum concentration to remove the solvent, pouring cold water into residues, stirring, performing suction filtration, adjusting the pH value of the filtrate with hydrochloric acid, performing suction filtration, and drying to obtain 5-nitrosalicylic acid; and 3) adding stannous chloride dihydrate, concentrated hydrochloric acid, the 5-nitrosalicylic acid and ethanol, carrying out vacuum concentration after the reaction is finished, dissolving residues in water, adjusting the pH value with a concentrated hydrochloric acid solution, standing for crystallization, carrying out suction filtration, washing filter cake with water, and drying to obtain mesalazine. No isomer is generated, and the yield is high; the method does not need high-temperature and high-pressure conditions; the reaction cost is low; and raw materialsand auxiliary materials with high toxicity and heavy environmental pollution are not used.
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(2020/08/25)

Catalytic oxidation of alcohols and alkyl benzenes to carbonyls using Fe3O4?SiO2?(TEMPO)-: Co -(Chlorophyll-CoIII) as a bi-functional, self-co-oxidant nanocatalyst
Chlorophyll b was extracted from heliotropium europaeum plant, demetalated, allylated and grafted to acrylated TEMPO through a copolymerization protocol. Then, the chlorophyll monomers were coordinated to Co ions, immobilized on magnetic nanoparticles and the resulting hybrid was used as a powerful catalyst for a variety of oxidation reactions. By using the present method, oxidation of benzylic alcohols and alkyl benzenes to carbonyls was accomplished in water under aerobic conditions. Moreover, direct oxidation of alcohols to carboxylic acids was performed by adding NaOCl to the mixture. All entries were oxidized to the corresponding desired product with high to excellent yields and up to 97% selectivity. The catalyst was thoroughly characterized by CV, TGA, VSM, XRD, XPS, DLS, FE-SEM, TEM, UV-Vis, EDX, and BET analyses. The activity of the catalyst was investigated by applying various components of the catalyst to the oxidation model separately. The reasonable mechanisms are suggested based on the cooperation between the TEMPO groups and cobalt(iii) (or Co(iv)) sites on the catalyst. The catalyst could be recovered and reused for at least 7 consecutive recycles without any considerable reactivity loss. This journal is
Hamah-Ameen, Baram Ahmed,Kazemnejadi, Milad,Mahmoudi, Boshra,Rostami, Amin
p. 6600 - 6613
(2020/11/16)

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)

Fe3O4@SiO2@Im[Cl]Mn(III)-complex as a highly efficient magnetically recoverable nanocatalyst for selective oxidation of alcohol to imine and oxime
An efficient and environmentally friendly oxidation process for the one-pot preparation of oxime, imine and carbonyl compounds through alcohol oxidation in the presence of H2O2 and/or O2 have been developed by a melamine-Mn(III) Schiff base complex supported on Fe3O4@SiO2–Cl nanoparticles, named as Fe3O4@SiO2@Im[Cl]Mn(III)-complex nanocomposite, at room temperature. Direct oxidation of alcohol to carboxylic acid was performed using the catalyst in the presence of molecular O2 at room temperature in a different approach. The oxidation products were obtained with excellent yields and high TOFs. The properties of the catalyst were characterized by Fourier transform infrared spectroscopy (FTIR), elemental analysis (C, H, N), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), inductive coupled plasma (ICP), cyclic voltammetry (CV), nuclear magnetic resonance (1H & 13C NMR), vibration sample magnetometer (VSM), Brunauer– Emmett–Teller (BET) and differential pulse voltammetry (DPV) analyses. The mechanism of the oxidation processes was investigated for the both H2O2 and O2 oxidants. The role of the imidazolium moiety in the catalyst as a secondary functionality was investigated. Chemoselectivity behavior of the catalyst was studied by some combinations. The catalyst could be recycled from the reaction mixture by a simple external magnet and reused for several times without any considerable reactivity loss.
Kazemnejadi, Milad,Alavi, Seyyedeh Ameneh,Rezazadeh, Zinat,Nasseri, Mohammad Ali,Allahresani, Ali,Esmaeilpour, Mohsen
p. 230 - 249
(2019/03/28)

Cathepsin B inhibitors: Further exploration of the nitroxoline core
Human cathepsin B is a cysteine protease with many house-keeping functions, such as intracellular proteolysis within lysosomes. Its increased activity and expression have been strongly associated with many pathological processes, including cancers. We present here the design and synthesis of novel derivatives of nitroxoline as inhibitors of cathepsin B. These were prepared either by omitting the pyridine part, or by modifying positions 2, 7, and 8 of nitroxoline. All compounds were evaluated for their ability to inhibit endopeptidase and exopeptidase activities of cathepsin B. For the most promising inhibitors, the ability to reduce extracellular and intracellular collagen IV degradation was determined, followed by their evaluation in cell-based in vitro models of tumor invasion. The presented data show that we have further defined the structural requirements for cathepsin B inhibition by nitroxoline derivatives and provided additional knowledge that could lead to non-peptidic compounds with usefulness against tumor progression.
Sosi?, Izidor,Mitrovi?, Ana,?uri?, Hrvoje,Knez, Damijan,Brodnik ?ugelj, Helena,?tefane, Bogdan,Kos, Janko,Gobec, Stanislav
supporting information
p. 1239 - 1247
(2018/03/05)

Rare earth fluorescent material Eu(5-nsa)3(phen) complex and preparation method thereof
The invention provides ternary rare earth complex fluorescent material Eu(5-nsa)3(phen).3H2O (5-nsa is 5-nitrosalicylic acid, phen is o-phenanthroline) and a preparation method thereof, and belongs tothe technical field of fluorescent materials. The preparation method is characterized in that the 5-nitrosalicylic acid is synthesized from salicylic acid as a raw material and acetone as a solvent,and the ternary rare earth complex is synthesized by adding a second ligand (o-phenanthroline) and a rare earth metal ion (Eu) into the 5-nitrosalicylic acid, with a molecular formula being Eu(C7H4O5N)3(C12H8N2).3H2O. The obtained complex, a new rare earth luminescent material, has three fluorescence emission peaks at 463 nm, 602 nm and 623 nm, respectively, under the maximum excitation wavelengthof 400 nm. The luminescence mode of the complex is the integrated luminescence of ligands and rare earth ions. The preparation method is simple in preparation process, simple and convenient in operation and good in product fluorescence characteristics.
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Paragraph 0012; 0013

(2018/11/03)

A US salad qin industrial preparation method (by machine translation)
The invention discloses a US salad qin industrial preparation method, characterized in that the preparation method is as follows: 1) to 2 - chloro - 5 - nitro-benzoic acid (I) as the starting material, the addition of a base, in a certain temperature lower substitution reaction to produce 2 - hydroxy - 5 - nitro-benzoic acid (intermediate II); 2) a certain pressure and temperature, and the catalyst, under alkaline conditions, for the finished product to the United States of Raney nickel reduction of nitro salad qin. The process of the invention the synthesis cost is low, mild reaction conditions, the whole process uses water as solvent, without the use of toxic reagent, catalyst recycled, the whole process of the green production; the product obtained by the process for high yield, with better purity. (by machine translation)
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Paragraph 0015; 0018

(2018/03/24)

A 5 - nitro salicylic acid synthesis method (by machine translation)
The invention belongs to the field of fine chemicals, in particular to a micro-reactor in order to continuous process of synthesizing 5 - nitro salicylic acid, which is characterized in that the two unit feeding mode, the pump segment and the substrate into the micro-reactor and nitration, the reaction temperature is controlled 55 - 75 °C, the residence time in the reactor 20 - 40 the s, and the resulting reaction mixture rapidly into the countercurrent extraction equipment, continuous liquid aqueous phase and organic phase are collected; the nitrating agent is sulfuric acid, nitric acid mixture, sulfuric acid and nitric acid mole ratio 3 - 4; the substrate is the nitration of salicylic acid and organic solvent solution; said reaction in the nitric acid salicylic acid molar ratio of 1.1 - 1.3. The reaction time of this invention greatly short the prior art 3 hours, using a continuous synthetic method, with the prior intermittent kettle drops compared with the processing technology, more accurate instantaneous matching of materials, reaction is stable, the operation is convenient. (by machine translation)
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Paragraph 0016; 0017; 0018; 0019

(2017/12/30)

Novel substituted sulfamide compound, preparation method and application thereof as PTP1B inhibitor
The invention relates to a novel substituted sulfamide compound of a structure of a formula I as shown in the description, a pharmaceutically acceptable salt of the novel substituted sulfamide compound, a preparation method, and relates to a medicinal composition comprising the compound of the formula I or a pharmaceutically acceptable salt of the compound. The compound of the formula I or the pharmaceutically acceptable salt of the compound has activity of inhibiting protein tyrosine phosphatase 1B (PTP1B), so that the compound or the pharmaceutically acceptable salt of the compound has an application of preparing a medicine for preventing/treating symptoms or diseases such as hyperglycemia and type-2 diabetes.
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Paragraph 0019; 0023

(2017/06/28)

METHOD FOR SPECIFIC CLEAVAGE OF C Alpha-C BOND AND SIDE CHAIN OF PROTEIN AND PEPTIDE, AND METHOD FOR DETERMINING AMINO ACID SEQUENCE
The present invention provides a method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain of a protein and a peptide, and a method for determining amino acid sequences of protein and peptide. A method for specifically cleaving a Cα-C bond of a peptide backbone and/or a side chain bond of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of at least one hydroxynitrobenzoic acid selected from the group consisting of 3-hydroxy-2-nitrobenzoic acid, 4-hydroxy-3-nitrobenzoic acid, 5-hydroxy-2-nitrobenzoic acid, 3-hydroxy-5-nitrobenzoic acid, and 4-hydroxy-2-nitrobenzoic acid. A method for determining an amino acid sequence of a protein or a peptide, comprising irradiating a protein or a peptide with laser light in the presence of the above specific hydroxynitrobenzoic acid to specifically cleave a Cα-C bond of a peptide backbone and/or a side chain bond, and analyzing generated fragment ions by mass spectrometry.
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(2017/12/15)

Preparation method of 5-aminosalicylic acid
The invention discloses a preparation method of 5-aminosalicylic acid. The method comprises the following steps: 1, preparing 5-nitrosalicylic acid: pre-incubating a salicylic acid solution used as a material 1, a concentrated nitric acid solution used as a material 2 and concentrated sulfuric acid used as a material 3 to a reaction temperature, mixing and reacting the material 1, the material 2 and the material 3, and post-processing the obtained reaction product to obtain purified 5-nitrosalicylic acid; and 2, preparing 5-aminosalicylic acid: dissolving the purified 5-nitrosalicylic acid in a solvent, adding Na2CO3 and a catalyst PdC to obtain a material 4, and carrying out pre-incubation catalytic hydrogenation to reduce the 5-nitrosalicylic acid into 5-aminosalicylic acid. The method has the advantages of simplicity in operation, controllable heat release, short production period, good area selectivity, environmental protection and safety, and realization of high yield and high purity of the finally obtained product.
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Paragraph 0041; 0042; 0043; 0044

(2017/07/22)

Novel urea protein tyrosine phosphatase 1B inhibitor, and preparation method, pharmaceutical composition and application thereof
The invention relates to novel urea compounds with a structure as shown in a general formula I in the specification or pharmaceutically acceptable salts thereof, wherein the urea compounds and the pharmaceutically acceptable salts thereof can be used as a novel inhibitor of protein tyrosine phosphatase (PTP) 1B. The invention also relates to a pharmaceutical composition containing the compounds as shown in the general formula I or the pharmaceutically acceptable salts of the compounds. The compounds as shown in the general formula I or the pharmaceutically acceptable salts thereof have the effect of inhibiting the activity of the protein tyrosine phosphatase 1B (PTP1B), and can be applied in preparation of drugs capable of preventing and/or treating symptoms or diseases like hyperglycemia and type 2 diabetes.
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Paragraph 0027

(2017/01/09)

5-[3-(2,5-diethoxy-4-methylsulfonyl-benzyl)-ureido]-2-ethoxylmethyl benzoate new compound and preparation method and application thereof
The invention provides a new compound. The name of the compound is 5-[3-(2,5-diethoxy-4-methylsulfonyl-benzyl)-ureido]-2-ethoxylmethyl benzoate; molecular weight of the compound is 509.5; and structure of the compound is as shown in the structural formula (compound 1). Meanwhile, the invention provides a preparation method of the compound 1. The compound provided by the invention has good drug-likeness and can be used in the research field of new drugs, especially in the research field of type-II diabetes innovative drugs.
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Paragraph 0010

(2017/05/02)

COMPOSITIONS AND METHODS FOR THE TREATMENT OF INFLAMMATORY BOWEL DISEASE
The invention relates to the compounds of formula I and formula II or its pharmaceutical acceptable salts, as well as polymorphs, solvates, enantiomers, stereoisomers and hydrates thereof. The pharmaceutical compositions comprising an effective amount of compounds of formula I or formula II; and methods for treating or preventing inflammatory bowel disease may be formulated for oral, buccal, rectal, topical, transdermal, transmucosal, intravenous, parenteral administration, syrup, or injection. Such compositions may be used to treatment of gastrointestinal diseases and inflammation such as inflammatory bowel disease, ulcerative colitis, mild-to-moderate Crohn's disease, rheumatoid arthritis, inflammatory arthritis, psoriatic arthritis, liver cirrhosis and idiopathic urticaria.
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Paragraph 0129; 0130

(2016/06/01)

Compositions and methods for the treatment of inflammatory bowel disease
The invention relates to the compounds of formula I and formula II or its pharmaceutical acceptable salts, as well as polymorphs, solvates, enantiomers, stereoisomers and hydrates thereof. The pharmaceutical compositions comprising an effective amount of compounds of formula I or formula II; and methods for treating or preventing inflammatory bowel disease may be formulated for oral, buccal, rectal, topical, transdermal, transmucosal, intravenous, parenteral administration, syrup, or injection. Such compositions may be used to treatment of gastrointestinal diseases and inflammation such as inflammatory bowel disease, ulcerative colitis, mild-to-moderate Crohn's disease, rheumatoid arthritis, inflammatory arthritis, psoriatic arthritis, liver cirrhosis and idiopathic urticaria.
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Page/Page column 39; 40; 41

(2016/12/16)

A versatile approach for the synthesis of para -substituted arenes via palladium-catalyzed C-H functionalization and protodecarboxylation of benzoic acids
While a great number of ortho C-H functionalization reactions have been developed and several breakthroughs have been achieved in meta C-H activation, para C-H functionalization is still in its infancy stage. In this article, a versatile strategy for the synthesis of para-substituted arenes has been developed via a tandem process consisting of palladium-catalyzed C-H functionalization and subsequent copper-catalyzed protodecarboxylation of benzoic acids. Both electron-withdrawing and electron-donating functionalities can be introduced into the para positions of arenes bearing a variety of substituents.
Pan, Shulei,Zhou, Bo,Zhang, Yanghui,Shao, Changdong,Shi, Guangfa
supporting information
p. 277 - 281
(2016/01/20)

Antiphlogistic enteropathy and method for treating dermatopathy compsn.
The invention relates to the compounds of formula I and formula II or its pharmaceutical acceptable salts, as well as polymorphs, solvates, enantiomers, stereoisomers and hydrates thereof. The pharmaceutical compositions comprising an effective amount of compounds of formula I or formula II; and methods for treating or preventing inflammatory bowel disease may be formulated for oral, buccal, rectal, topical, transdermal, transmucosal, intravenous, parenteral administration, syrup, or injection. Such compositions may be used to treatment of gastrointestinal diseases and inflammation such as inflammatory bowel disease, ulcerative colitis, mild-to-moderate Crohn's disease, rheumatoid arthritis, inflammatory arthritis, psoriatic arthritis, liver cirrhosis and idiopathic urticaria.
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Paragraph 0103-0105; 0392-0394

(2018/10/19)

Methyl salicylate as a selective methylation agent for the esterification of carboxylic acids
Methyl salicylate is a selective and inexpensive methylating agent for the esterification of carboxylic acids with a wide range of functional group tolerance. The intramolecular hydrogen bonds between the carboxylate and hydroxyl groups in methyl salicylate are essential for the transformation. Allyl, benzyl, methallyl, and propargyl salicylates can also be used as alkylating agents for the preparation of the corresponding alkyl carboxylates.
Chen, Si,Jia, Lei,Li, Xiaonan,Luo, Meiming
p. 263 - 268
(2014/03/21)

Design, synthesis and evaluation of 3-(2-Aminoheterocycle)-4- benzyloxyphenylbenzamide derivatives as BACE-1 inhibitors
Three series of 3-(2-aminoheterocycle)-4-benzyloxyphenylbenzamide derivatives, 2-aminooxazoles, 2-aminothiazoles, and 2-amino-6H-1,3,4-thiadizines were designed, synthesized and evaluated as β-secretase (BACE-1) inhibitors. Preliminary structure-activity relationships revealed that the existence of a 2-amino-6H-1,3,4-thiadizine moiety and α-naphthyl group were favorable for BACE-1 inhibition. Among the synthesized compounds, 5e exhibited the most potent BACE-1 inhibitory activity, with an IC50 value of 9.9 μM and it exhibited high brain uptake potential in Madin-Darby anine kidney cell lines (MDCK) and a Madin-Darby canine kidney-multidrug resistance 1 (MDCK-MDR1) model.
Shangguan, Shihao,Wang, Fei,Liao, Yong,Yu, Haiping,Li, Jia,Huang, Wenhai,Hu, Haihong,Yu, Lushan,Hu, Yongzhou,Sheng, Rong
p. 3577 - 3594
(2013/04/24)

Efficient method for the oxidation of aldehydes and diols with tert-butylhydroperoxide under transition metal-free conditions
An efficient, mild, and simple protocol is presented for the oxidation of aldehydes and diols to carboxylic acids utilizing 70% aq TBHP as oxidant and t-BuOK as additive. The oxidation of aldehydes could be achieved by two methods under aqueous medium. Excellent yields of products were obtained in short reaction times. Notably, the products were isolated by simple filtration technique and do not involve chromatographic separation. These reactions may prove to be valuable alternatives to traditional metal-mediated oxidations. Oxidation does not require any transition metals or organic solvents in reaction, making this protocol green.
Shaikh, Tanveer Mahammadali,Hong, Fung-E
p. 8929 - 8935
(2013/09/23)

The reaction of hydroxylamine with aspirin
Hydroxylamine reacts with aspirin in aqueous solution at 25 °C predominantly through oxygen, to give O-acetylhydroxylamine as the initial product (Scheme 3). The reaction is much faster than the intramolecular general base catalysed hydrolysis of the carboxylate anion, as it is also for the CO2H form of aspirin. Both reactions are faster than expected, consistent with moderate activation and/or proton transfer catalysis of hydroxylaminolysis by both CO2- and CO2H groups. Calculations support oxygen attack as the preferred reaction, but do not permit a clear choice between mechanisms involving NH2OH and +NH3-O- as the effective nucleophile. ARKAT-USA, Inc.
Medeiros, Michelle,Souza, Bruno S.,Orth, Elisa S.,Brandao, Tiago A. S.,Rocha, Willian,Kirby, Anthony J.,Nome, Faruk
scheme or table
p. 461 - 476
(2011/10/05)

Mild and efficient nitration of aromatic compounds mediated by transitionmetal complexes
Aromatic compounds were efficiently nitrated under facile reaction conditions by employing 69% nitric acid catalyzed by transition-metal complexes such as [Co(NH3)5Cl]Cl2, [Cu(NH 3)4]SO4, Mn(acac)3, [Ni(NH 3)6]Cl2, [Ni(en)3]S 2O3, and Hg[Co(SCN)4]. The reaction was completed smoothly at room temperature and afforded corresponding mono-nitro derivatives in quantitative yield. This new method offers efficient and facile regioselective mononitration of aromatic compounds. Taylor & Francis Group, LLC.
Abdulla,Amina,Kumar, Y. Arun,Arifuddin,Rajanna
experimental part
p. 2946 - 2951
(2011/09/12)

Tocotrienamines and tocopheramines: Reactions with radicals and metal ions
The antioxidant activity of vitamin E (VE) homologs a, c and d-tocotrienamines (4b-6b), never studied before, and a, c and d-tocopheramines (4a-7a) was investigated by means of different total antioxidant capacity (TAC) tests. In all the test model systems, compounds 4a-7a and 4b-6b showed similar or higher TAC values than the parental vitamin E forms and their physiological metabolites. α-Homologs of VE amines showed markedly higher activity than the VE congeners in the TEAC test, which is tailored for liposoluble antioxidants, while c-homologs of the amine analogs showed higher activity in the FRAP tests. Kinetics analysis of the reaction with DPPH showed higher second order rate k for 4a than for α-tocopherol (1a). α-Tocopherolquinone 1f was the common main oxidation product for both 1a and α-tocopheramine (4a) exposed to ferric ions or DPPH, and the implied oxidative deamination of 4a was accompanied by a nitration reaction of phenolic substrates that were added to the reaction medium. Possible mechanisms of these reactions were studied.
Galli, Francesco,Mazzini, Francesco,Bamonti, Luca,Gille, Lars,B?hmdorfer, Stefan,Piroddi, Marta,Netscher, Thomas,Kelly, Frank J.,Rosenau, Thomas
experimental part
p. 6483 - 6491
(2011/12/04)

Fast and efficient nitration of salicylic acid and some other aromatic compounds over H3PO4/TiO2-ZrO2 using nitric acid
TiO2-ZrO2 (1/1)-surf with Ti and Zr molar ratio of 1/1 was prepared with surfactant through a sol-gel method. The optimum experimental condition was investigated for nitration of salicylic acid. Then, a number of nitration reactions were carried out with a variety of aromatic compounds in the optimum condition. The 25 wt% H3PO4/TiO2-ZrO2 (1/1)-surf catalyst showed good selectivity and yield in a short time for the nitration of salicylic acid and some other aromatic compounds.
Kalbasi, Roozbeh Javad,Massah, Ahmad Reza,Zamani, Farzad,Hamid, Javaherian Naghash
experimental part
p. 397 - 403
(2010/10/20)

Improved synthesis of 3-nitrosalicylic acid
Nitration of salicylic acid using 2-propyl nitrate/sulfuric acid/tetrabutylammonium hydrogensulfate/dichloromethane/water yielded a mixture of 3-nitro and 5-nitrosalicylic acids in the ratio 56:44. Pure potassium 3-nitrosalicylate was crystallized and converted to 3-nitrosalicylic acid in 30% overall yield. Copyright
Hummel, Michael,Laus, Gerhard,Nerdinger, Sven,Schottenberger, Herwig
experimental part
p. 3353 - 3357
(2010/12/24)

NITRATION OF ACTIVATED AROMATICS IN MICROREACTORS
The invention relates to the nitration of aromatic or heteroaromatic compounds, wherein an activated aromatic or heteroaromatic compound and a nitration agent, optionally in the presence of a solvent, are mixed intensely in a microreactor, and wherein the proportion of the nitration agent to the activated aromatic or heteroaromatic compound, the concentration of nitration agent in the reaction mixture, and the temperature are selected at levels such high that the nitration begins autocatalytically, and wherein the nitration product is obtained after leaving the microreactor and, optionally after an after-reaction time outside the microreactor.
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Page/Page column 6; 8

(2010/12/29)

Efficient and facile method for the nitration of aromatic compounds by nitric acid in micellar media
Aromatic compounds were efficiently nitrated under mild reaction conditions by employing HNO3 in the presence of anionic (sodium dodecyl sulfate, SDS), cationic (cetyl trimethyl ammonium bromide, CTAB), and nonionic (Triton-X 100) micelles. The reaction rapidly afforded corresponding mononitro derivatives in fair to good yields with high regioselectivity. This new method offers an environmentally safe reaction condition to minimize the waste products.
Sana,Tasneem,Ali, M. Moazzam,Rajanna,Saiprakash
experimental part
p. 2949 - 2953
(2009/12/03)

Iron-promoted ortho-And/or ipso-hydroxylation of benzoic acids with H 2O2
Regioselective hydroxylation of aromatic acids with hydrogen peroxide proceeds readily in the presence of iron(II) complexes with tetradentate aminopyridine ligands [FeII(BPMEN)-(CH3CN) 2](ClO4)2 (1) and [FeII(TPA)- (CH3CN)2](OTf)2 (2), where BPMEN=N, N'-dimethyl-N, N'-bis(2-pyridylmethyl)-1,2-ethylenediamine, TPA=tris-(2- pyridylmethyl)amine. Two cis-sites, which are occupied by labile acetonitrile molecules in 1 and 2, are available for coordination of H2O 2 and substituted benzoic acids. The hydroxylation of the aromatic ring occurs exclusively in the vicinity of the anchoring carboxylate functional group: ortho-hydroxylation affords salicylates, whereas ipso-hydroxylation with concomitant decarboxylation yields phenolates. The outcome of the substituent directed hydroxylation depends on the electronic properties and the position of substituents in the molecules of substrates:3-substituted benzoic acids are preferentially ortho-hydroxylated, whereas 2-and, to a lesser extent, 4-substituted substrates tend to undergo ipso-hydroxylation/decarboxylation. These two pathways are not mutually exclusive and likely proceed via a common intermediate. Electron-withdrawing substituents on the aromatic ring of the carboxylic acids disfavor hydroxylation, indicating an electrophilic nature for the active oxidant. Complexes 1 and 2 exhibit similar reactivity patterns, but 1 generates a more powerful oxidant than 2. Spectroscopic and labeling studies exclude acylperoxoiron(III) and FeIV=O species as potential reaction intermediates, but strongly indicate the involvement of an FeIII-OOH intermediate that undergoes intramolecular acid-promoted heterolytic O-O bond cleavage, producing a transient iron(V) oxidant.
Makhlynets, Olga V.,Das, Parthapratim,Taktak, Sonia,Flook, Margaret,Mas-Balleste, Ruben,Rybak-Akimova, Elena V.,Que Jr., Lawrence
experimental part
p. 13171 - 13180
(2010/07/03)

INHIBITORS OF STEAROYL-COA DESATURASE
Provided herein are compounds of the formula (I): as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment of diseases such as, for example, obesity.
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(2009/06/27)

Continuous flow nitration of salicylic acid
Continuous flow nitration of salicylic acid using HNO3/AcOH was studied in the SS316 tubular microreactor. At specific reaction conditions, complete conversion of the reactant was achieved in less than 7 min. It yielded only mononitro derivatives with a higher selectivity of 5-nitrosalicylic acid. Presence of the lower amount of acetic acid in the reaction mixture was seen to be detrimental, leading to precipitation of the desired product (5-nitrosalicylic acid). Reaction at higher temperatures yielded byproducts. The continuous mode operation using the system comprising the microdevices was demonstrated for 2 h with consistent composition at the outlet
Kulkarni, Amol A.,Nivangune, Nayana T.,Kalyani, Vishwanath S.,Joshi, Ramesh A.,Joshi, Rohini R.
p. 995 - 1000
(2013/01/03)

Process for the synthesis of hydroxy aromatic acids
Hydroxy aromatic acids are produced in high yields and high purity (>95%) from halogenated aromatic acids in a reaction mixture containing a copper source and a ligand that coordinates to copper.
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Page/Page column 20-21

(2008/06/13)

Nitration of some aromatic compounds by sodium nitrate in the presence of benzyltriphenylphosphonium peroxodisulfate
A simple, mild, and regioselective method for the nitration of some aromatic compounds using sodium nitrate in the presence of benzyltriphenylphosphonium peroxodisulfate in acetonitrile as solvent is reported. Mild reaction conditions and good to excellent yields of the products are the noteworthy advantages of the method. Copyright Taylor & Francis Group, LLC.
Tajik, Hassan,Zolfigol, Mohammad Ali,Albadi, Jalal,Eslami, Ramin
p. 2771 - 2776
(2008/02/12)

Microwave promoted rapid nitration of phenolic compounds with calcium nitrate
Highly accelerated and safe nitration of phenolic compounds has been found to be feasible with a mixture of calcium nitrate and acetic acid as an efficient nitration agent under brief microwave irradiation. This method is compatible with the green chemistry approach because calcium salts-the inorganic byproducts-can be useful agrochemicals rather than waste chemicals. Commercially available 15N-labeled calcium nitrate is convenient for the preparation of 15N-labeled compounds for metabolic studies and mass spectrometry. This safe nitration method can be included in laboratory experiments for high school and college students.
Bose, Ajay K.,Ganguly, Subhendu N.,Manhas, Maghar S.,Rao, Sheetal,Speck, Jeffrey,Pekelny, Uri,Pombo-Villars, Esteban
p. 1885 - 1888
(2007/10/03)

Cold microwave chemistry: synthesis using pre-cooled reagents
A novel experimental procedure for chemical reactions has been devised that involves mixing and then freezing the reagents (organic solvent-free) to a sub-zero temperature such as -30 °C. This frozen mixture is exposed to microwave irradiation for a brief period of time. The use of pre-cooled reagents may give a single product not obtained by traditional microwave irradiation at room temperature. Interestingly, such a product may provide information about mechanisms by identifying the first step of a multiple step reaction.
Bose, Ajay K.,Ganguly, Subhendu N.,Manhas, Maghar S.,He, William,Speck, Jeffrey
p. 3213 - 3215
(2007/10/03)

Salicylic acid nitration by means of nitric acid/acetic acid system: Chemical and kinetic characterization
The nitration of salicylic acid by means of HNO3/AcOH is investigated, and the results are compared with those obtained using different nitrating systems: HNO3/H2SO4/H2O (mixed acid), HNO3/Ac2O/AcOH, aqueous HNO3 (70% by weight) at 343 K. Little differences are found in terms of yield of the desired product (5-nitrosalicylic acid) among HNO3/AcOH mixture, mixed acid, and HNO3/Ac2O/AcOH systems, aqueous HNO 3 giving the poorest results. However according to the data collected during the present investigation the use of the system HNO3/AcOH presents some advantages with respect to the others for the separation and purity of desired product, waste minimization, and safety improvements. The reaction kinetics for the nitration of salicylic acid with this system is also investigated. A global second-order kinetic law (one for the substrate, one for nitric acid) is used in the analysis of the data collected for the formation of the two mononitroderivatives (3-nitro- and 5-nitrosalicylic acids) and of the side product 2-nitrophenol.
Andreozzi, Roberto,Canterino, Marisa,Caprio, Vincenzo,Di Somma, Ilaria,Sanchirico, Roberto
p. 1199 - 1204
(2012/12/23)

Nitration of aromatic compounds by Zn(NO3)2· 2N2O4 and its charcoal-supported system
Zn(NO3)2·N2O4 and its charcoal supported system were found to be efficient nitrating agents. Mononitration of aromatic compounds such as benzene, alkyl benzenes, halobenzenes, nitrobenzene, anisol, and the highly selective mono-, di-, and trinitration of phenol, and dinitraion of substituted phenols were also performed in the presence of these reagents.
Iranpoor, Nasser,Firouzabadi, Habib,Heydari, Reza,Shiri, Morteza
p. 263 - 270
(2007/10/03)

The cleavage of heterocyclic compounds in organic synthesis II [1] use of 5-nitroisatine for synthesis of various nitrogenous heterocycles
The reactions of 5-nitroisatine were studied with nucleophiles like heterocyclic amines and alkaline hydroxide. With the use of alkaline hydroxide it was converted into 2-amino-5-nitrophenylglyoxylic acid 2, with piperidine, morpholine and carbethoxypiperazine to its amides 4a-4c or by oxidation to 5-nitroanthranilic acid 7. This acid was used for synthesis of 3-hydroxy-6-nitro-2-phenyl-1H-quinolin-4-one 10. Semicarbazone of 5-nitroisatine 11 was converted to 5-(2-amino-5-nitrophenyl)-2,3,4,5-tetrahydro-1,2,4- triazine-3,5-dione 12. Cyclocondensation of this compound to afford 8-nitro-2,3-dihydro-5H-[1,2,4]triazino-[5,6-b]indol-3-one 13 was unsuccessful.
Hlavac, Jan,Soural, Miroslav,Hradil, Pavel,Frysova, Iveta,Slouka, Jan
p. 633 - 636
(2007/10/03)

Synthesis of salicylic acid derivatives in presence of ultrasonic irradiation using water as solvent
An improved synthesis of salicylic acid using ultrasonic irradiation and water as solvent can be achieved with copper and pyridine as catalysts. A number of salicylic acids were prepared in good yield and in a short reaction time.
Docampo Palacios, Maite L.,Pellon Comdom, Rolando F.
p. 1783 - 1787
(2007/10/03)

Synthesis of salicylic acid derivatives from the corresponding 2-chlorobenzoic acid using water as solvent
An improved synthesis of salicylic acid using water as solvent can be achieved using the Ullmann-Goldberg reaction conditions in presence of pyridine as cocatalyst. A number of salicylic acids were prepared in good yield.
Pellon Comdom, Rolando F.,Docampo Palacios, Maite L.
p. 2055 - 2059
(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)

Micellar catalysis of organic reactions. Part 37. A comparison of the catalysis of ester and amide hydrolysis by copper-containing micelles
The hydrolysis of a number of nitroactivated esters and amides has been studied in the presence of copper-containing metallomicelles at neutral pH. The relative rates of hydrolysis in the pure metallomicelle and in co-micelles with either cetyltrimethylammonium bromide (ctab) or Triton X-100 depends on the hydrophobicity of the substrate and whether it is completely solubilized by the copper micelle. Thus it depends on the concentration of the copper micelle. At low concentrations of copper micelle (0.2 mM) where the substrate is incompletely solubilized, the reaction is faster when 2 mM crab is added. At higher concentrations (>0.6 mM) where the substrate may be almost completely solubilized by the copper micelle, the reaction is slower when 2 mM crab is added. For ester hydrolysis the presence of either a carboxylic acid group or a heterocyclic nitrogen atom close to the reaction centre resulted in much larger catalysis by the metallomicelle than for model compounds without these additional groups. It is postulated that these groups coordinate with the metal ion and thus present the reaction centre close to a metal-bound hydroxyl resulting in a significant increase in the rate of bond formation, which is the rate-determining step for ester hydrolysis. For amide hydrolysis the presence of a carboxyl group ortho to the reaction centre did not lead to larger catalysis by the copper micelle than for the compound without this group. This difference is attributed to the different rate-determining steps for amide and for ester hydrolysis.
Broxton,Nasser
p. 202 - 206
(2007/10/03)

Substrate-assisted catalysis in glycosidases
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Wang, Qingping,Withers, Stephen G.
p. 10137 - 10138
(2007/10/02)

A Mild Oxidation of Aromatic Amines
Several primary aromatic amines have been converted to the corresponding nitro compounds in good yields.The oxidant was oxone (potassium peroxymonosulfate) and the reactions were performed in 5 to 20percent aqueous acetone and buffered with sodium bicarbonate.
Webb, Kevin S.,Seneviratne, Viran
p. 2377 - 2378
(2007/10/02)

Multiple behaviors in the cleavage of aryl alkanoates by αand β-cyclodextrins. Processes involving two molecules of cyclodextrin
The kinetics of ester cleavage of 4-carboxy-2- nitrophenyl alkanoates (1) (C2-C8) and of 2- carboxy-4-nitrophenyl alkanoates (2) (C2, C4,C6, C8) in an aqueous phosphate buffer (pH 11.7) containing α- orβ-cyclodextrin (α- or β-CD) show various types of behavior. Depending on the ester, its acyl chain, and the CD, the kinetics show acceleration (with or without saturation), retardation, acceleration and retardation, retardation and acceleration, or two kinds of acceleration. However, this diversity can be rationalized with simple reaction schemes. Short-chain esters mainly react conventionally through binary CD-ester complexes. For longer chains, some ester/CD combinations exhibit nonproductive 2:1 (CD:ester) binding, whereas other combinations show a cleavage process involving two CD molecules. The latter is most likely due to the attack of a CD (anion) on the 1:1 CD-ester complex or to reaction within a weak 2:1 complex. Modes of transition-state binding are probed using the pseudoequilibrium constants (KTS) introduced in earlier work (Carbohydr. Res. 1989, 192, 181).
Tee, Oswald S.,Du, Xian-Xian
p. 620 - 627
(2007/10/02)

The Synthesis of Some 10-Phenylacridinium Salts and Related Compounds
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Acheson, R. Morrin,Birtwistle, David H.,Wyatt, Peter B.
p. 2762 - 2781
(2007/10/02)

Esterase-like activity of human serum albumin. IV. Reactions with substituted aspirins and 5-nitrosalicyl esters
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Kurono,Yamada,Hata,Okada,Takeuchi,Ikeda
p. 3715 - 3719
(2007/10/02)

Decarboxylative Nitration of Some Simple Hydroxybenzoic Acids Using Cerium(IV) Ammonium Nitrate
The mechanistic pathways proposed earlier in the Ce(IV) induced decarboxylation of aromatic acids have been examined in the light of new observations made.A simple, non-explosive, easy to control substitute to Bechman and Biermann's decarboxylative nitration is described and a plausible mechanism suggested.
Chawla, H. Mohindra,Mittal, Ram S.
p. 1129 - 1131
(2007/10/02)