- Nitration of deactivated aromatic compounds via mechanochemical reaction
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A variety of deactivated arenes were nitrated to their corresponding nitro derivatives in excellent yields under high-speed ball milling condition using Fe(NO3)3·9H2O/P2O5 as nitrating reagent. A radical involved mechanism was proposed for this facial, eco-friendly, safe, and effective nitration reaction.
- Wu, Jian-Wei,Zhang, Pu,Guo, Zhi-Xin
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supporting information
(2021/05/05)
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- Design, Synthesis, and Study of the Insecticidal Activity of Novel Steroidal 1,3,4-Oxadiazoles
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A series of novel steroidal derivatives with a substituted 1,3,4-oxadiazole structure was designed and synthesized, and the target compounds were evaluated for their insecticidal activity against five aphid species. Most of the tested compounds exhibited potent insecticidal activity against Eriosoma lanigerum (Hausmann), Myzus persicae, and Aphis citricola. Compounds 20g and 24g displayed the highest activity against E. lanigerum, showing LC50 values of 27.6 and 30.4 μg/mL, respectively. Ultrastructural changes in the midgut cells of E. lanigerum were detected by transmission electron microscopy, indicating that these steroidal oxazole derivatives might exert their insecticidal activity by destroying the mitochondria and nuclear membranes in insect midgut cells. Furthermore, a field trial showed that compound 20g exhibited effects similar to those of the positive controls chlorpyrifos and thiamethoxam against E. lanigerum, reaching a control rate of 89.5% at a dose of 200 μg/mL after 21 days. We also investigated the hydrolysis and metabolism of the target compounds in E. lanigerum by assaying the activities of three insecticide-detoxifying enzymes. Compound 20g at 50 μg/mL exhibited inhibitory action on carboxylesterase similar to the known inhibitor triphenyl phosphate. The above results demonstrate the potential of these steroidal oxazole derivatives to be developed as novel pesticides.
- Bai, Hangyu,Jiang, Weiqi,Li, Qi,Li, Tian,Ma, Shichuang,Shi, Baojun,Wu, Wenjun
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p. 11572 - 11581
(2021/10/12)
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- PROCESS FOR THE PREPARATION OF QUINOLONE BASED COMPOUNDS
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The present invention relates to an improved process for the preparation of quinolone based compounds of general formula (I) using intermediate compound of general formula (XII). Invention also provides an improved process for the preparation of compound of formula (I-a) using intermediate compound of formula (XII-a) and some novel impurities generated during process. Compounds prepared using this process can be used to treat anemia.
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Paragraph 0288-0289
(2019/12/06)
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- N-(5-Methyl-1,3-Thiazol-2-yl)-2-{[5-((Un)Substituted- Phenyl)1,3,4-Oxadiazol-2-yl]Sulfanyl}acetamides. Unique Biheterocycles as Promising Therapeutic Agents
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An electrophile, 2-bromo-N-(5-methyl-1,3-thiazol-2-yl)acetamide, was synthesized by the reaction of 5-methyl-1,3-thiazol-2-amine and bromoacetyl bromide in an aqueous medium. In a parallel scheme, a series of (un)substituted benzoic acids was converted sequentially into respective esters, acid hydrazides, and then into 1,3,4-oxadiazole heterocyclic cores. The electrophile was coupled with the aforementioned 1,3,4-oxadiazoles to obtain the targeted bi-heterocyles. Structural analysis of the synthesized compounds was performed by IR, EI-MS, 1H NMR, and 13C NMR. The enzyme inhibition study of these molecules was carried out against four enzymes, namely, acetylcholinesterase, butyrylcholinesterase, α-glucosidase, and urease. The interactions of these compounds with respective enzymes were recognized by their in silico study. Moreover, their cytotoxicity was also determined to find out their utility as possible therapeutic agents.
- Abbasi,Ramzan,Aziz-ur-Rehman,Siddiqui,Shah,Hassan,Seo,Ashraf,Mirza,Ismail
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p. 801 - 811
(2019/02/27)
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- Solvent- and Metal-free Oxidative Esterification of Aromatic Aldehydes Using Urea-2,2-dihydroperoxypropane as a New Solid Oxidant
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Urea-2,2-dihydroperoxypropane as a noble and solid gem-dihydroperoxide derivative was used to transform various aromatic aldehydes to their corresponding benzoate derivatives in the presence of HBr under mild conditions at room temperature in high yields and short reaction times.
- Khosravi, Kaveh,Khalaji, Kobra,Naserifar, Shirin
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p. 303 - 309
(2017/03/27)
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- Polymer supported Zn-salen complexes: An effective one-pot oxidative esterification of aldehydes to carboxylic esters
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Polymer-supported Zn-salen (PS-Zn-salen) complexes were synthesized, characterized and used as a catalyst for one-pot oxidative esterification of aldehydes with alcohols. The PS-Zn-salen heterogeneous catalyst exhibited a high-performance for the oxidative esterification of aldehydes to the corresponding methyl/ethyl esters using hydrogen peroxide as a green oxidant. Due to the synergistic effect of polymer support, the heterogeneous catalyst presented superior catalytic activity and afford 100% conversion of 3,4,5-trimethoxybenzaldehyde and 4-chlorobenzaldehyde to corresponding esters under optimized conditions. The different alcohol substrates study (viz. methyl alcohol, ethyl alcohol, allyl alcohol and benzyl alcohol) showed reasonable selectivity for esters, indicating the scope of the catalysts. Significantly, the synthesized complexes possess good hydrophobic/heterogeneous properties, which permit facile reclamation of the catalyst by using mere filtration. Moreover, the effect of counter anions of complex also studied which indicated that there is no appreciable influence on the conversion of product. The catalyst was reused up to 5th successive run with the average conversion of ester 87.4%. Mechanistic studies have recognized that this “one pot” direct oxidative esterification proceeds through acid formation, proven by a GC–MS. The catalyst is also found to be very stable, up to 280?°C, confirmed by the thermo gravimetric study.
- Balinge, Kamlesh Rudreshwar,Khiratkar, Avinash Ganesh,Bhagat, Pundlik Rambhau
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p. 1085 - 1095
(2017/08/08)
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- Synthesis, spectral analysis and antibacterial evaluation of 5-substituted-1,3,4-oxadiazol-2-yl 4-(4-methylpiperidin-1-ylsulfonyl)benzyl sulfides
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Owing to valuable biological activities of 1,3,4-oxadiazole, sulfamoyl and piperidine functionalities, some new 1-(4-{[(5-substituted-1,3,4-oxadiazol-2-yl) thio]methyl}benzene sulfonyl)-4-methylpiperidine (6a-o) derivatives have been introduced. The target molecules were synthesized from different aralkyl/aryl carboxylic acids, 1a-o, through a series of steps. First the compounds, 1a-o, were converted to heterocyclic 1,3,4-oxadiazole nucleophiles, 4a-o. Second an electrophile as 1-(4-bromomethylbenzenesulfonyl)-4-methylpiperidine (5) was synthesized from 4-methylpiperidine. Finally the target compounds, 6a-o, were prepared by reacting 4a-o with 5 in DMF and LiH. The final compounds were structurally elucidated by spectral data of IR, 1H-NMR and EI-MS. All the compounds were screened for their antibacterial evaluation and found to exhibit valuable results.
- Aziz-Ur-Rehman,Ahtzaz, Samreen,Abbasi, Muhammad Athar,Siddiqui, Sabahat Zahra,Rasool, Shahid,Ahmad, Irshad
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p. 3370 - 3375
(2017/05/22)
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- Zinc Complexes with Cyanoxime: Structural, Spectroscopic, and Catalysis Studies in the Pivaloylcyanoxime-Zn System
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Reaction of 2-hydroxyimino-4,4-dimethyl-3-oxo-pentanenitrile (common abbreviation HPiCO, pivaloyl-cyanoxime) with zinc sulfate in an aqueous solution results in the formation of the two new complexes: [Zn(PiCO){H(PiCO)2}(H2O)] (I) and tetranuclear Zn complex [Zn4(μ3-OH)2(PiCO)6 (H2O)4] (II). Both complexes were characterized by elemental analysis, IR- and UV-visible spectra, DSC/TGA studies, and X-ray analysis. In complex II, the PiCO- cyanoxime anion adopts three bidentate binding modes: O-monodentate, chelating (κ2), and bridging (2) coordinations. Also, the ligand represents the mixture of two diasteromers (cis-anti and cis-syn) that form five- and six-membered chelate rings with Zn atoms and cocrystallize in one unit cell at population of 0.57-0.43. There are two crystallographically different Zn-centers in the ASU, and two μ3-bridging hydroxo-groups arrange via inversion center the formation of an elegant tetranuclear complex. Each Zn atom has a molecule of coordinated water and is in the distorted octahedral environment. Because of the structural flexibility and multidentate propensity of the pivaloyl-cyanoxime, complex II may act as a structural model of naturally occurring Zn-containing enzymes. Indeed, compound I exhibits an efficient catalytic performance for transesterification reaction of various esters in ethanol under mild reaction conditions. Therefore, obtained results allow assignment of observed activity as green catalysis.
- Opalade, Adedamola A.,Karmakar, Anirban,Rúbio,Pombeiro, Armando J. L.,Gerasimchuk, Nikolay
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p. 13962 - 13974
(2017/11/24)
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- Synthesis of oxadiazoline and quinazolinone derivatives and their biological evaluation as nitric oxide synthase inhibitors
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The synthesis of two new families of compounds with oxadiazoline and quinazolinone structures and their in vitro biological evaluation as inhibitors of both neuronal and inducible nitric oxide synthases (nNOS and iNOS) are described. These derivatives have been obtained from cyclization of substituted benzohydrazides with acid anhydrides followed by reduction, using different synthetic procedures. Their structures were confirmed by high-resolution mass spectroscopy and 1H and 13C nuclear magnetic resonance data. In general, the assayed compounds show better inhibition values of nNOS than of iNOS, being 7d the most active derivative with a quinazolinone scaffold, and 6t the best oxadiazoline one and the best nNOS inhibitor of all tested compounds. The structure–activity relationships are discussed in terms of the effects of the substituents on both 2- and 3-positions of the heterocyclic rings.
- Pineda de las Infantas, M. José,Carrión, M. Dora,Chayah, Mariem,López-Cara, Luisa C.,Gallo, Miguel A.,Acu?a-Castroviejo, Darío,Camacho, M. Encarnación
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p. 1260 - 1273
(2016/07/06)
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- Design, synthesis, pharmacological evaluation and molecular docking studies of substituted oxadiazolyl-2-oxoindolinylidene propane hydrazide derivatives
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The manuscript describes design and synthesis of novel oxadiazolyl-2-oxoindolinylidene propane hydrazides as amide tethered hybrids of indole and oxadiazole and their evaluation for antiinflammatory and analgesic activity. The compounds were synthesized following five step reaction to yield fifteen derivatives as 3-(5-substituted-1,3,4-oxadiazol-2-yl)-N′-[2-oxo-1,2-dihydro-3Hindol-3-ylidene]propane hydrazides. The final derivatives 3-[5-(4-hydroxyphenyl)-1,3,4-oxadiazol-2-yl]-N′-[2-oxo-1,2-dihydro-3H-indol-3-ylidene]propane hydrazide and 3-[5-(4-methylphenyl)-1,3,4-oxadiazol-2-yl]-N′-[2-oxo-1,2-dihydro-3H-indol-3-ylidene]propane hydrazide were found to be highly promising molecules with severity index of 0.35 and 0.56, respectively, which is promising for an analgesic compound. The hydroxy and methyl substitution on phenyl ring system provided with active anti-inflammatory compounds having increase in reaction time of 84.11 and 83.17percent, respectively compared to standard drug at 85.84percent. Molecular docking studies exhibit comparable interaction with synthesized derivatives and standard drug having a dock score of -4.44 by the K-nearest neighbour genetic algorithm method.
- Kerzare, Deweshri,Chikhale, Rupesh,Bansode, Ratnadeep,Amnerkar, Nikhil,Karodia, Nazira,Paradkar, Anant,Khedekar, Pramod
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p. 1998 - 2010
(2016/11/03)
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- Synthesis of novel triazoles and a tetrazole of escitalopram as cholinesterase inhibitors
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A novel serie of escitalopram triazoles (60-88) and a tetrazole (89) have been synthesized and subjected to a study to establish the inhibitory potential of these compounds toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some selectivity in inhibition has been observed. The 4-chlorophenyl- (75, IC50, 6.71 ± 0.25 μM) and 2-methylphenyl- (70, IC50, 9.52 ± 0.23 μM) escitalopram triazole derivatives depicted high AChE inhibition, while 2-fluorophenyl- (76, IC50 = 4.52 ± 0.17 μM) and 4-fluorophenyl- (78, IC50 = 5.31 ± 0.43 μM) have found to be excellent BChE inhibitors. It has also been observed that ortho, meta and para substituted electron donating groups increase the inhibition, while electron withdrawing groups reduce the inhibition. Docking analyses of inhibitors with AChE have depicted the binding energies for 70 and 75 as ΔGbind -6.42 and -6.93 kcal/mol, respectively, while ligands 76 and 78 have shown the binding affinity ΔGbind -9.04 and -8.51 kcal/mol, respectively, for BChE.
- Mehr-Un-Nisa,Munawar, Munawar A.,Chattha, Fauzia A.,Kousar, Samina,Munir, Jawaria,Ismail, Tayaba,Ashraf, Muhammad,Khan, Misbahul A.
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p. 6014 - 6024
(2015/11/11)
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- Polymer supported Pd catalyzed carbonylation of aryl bromides for the synthesis of aryl esters and amides
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A polymer-anchored palladium(ii) catalyst was synthesized and characterized using various spectroscopic techniques. Its catalytic activity was evaluated for the alkoxycarbonylation and aminocarbonylation reactions. These carbonylation reactions were carried out for various substituted aryl bromides using alcohols and amines. Both the reactions were optimized by varying the bases, temperature and solvents. These experiments were carried out under high CO pressure. The catalyst was very stable and can be facilely recovered and reused six times without a significant decrease in its activity and selectivity. the Partner Organisations 2014.
- Islam, Sk Manirul,Ghosh, Kajari,Roy, Anupam Singha,Molla, Rostam Ali
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p. 38986 - 38999
(2014/11/07)
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- Inclusion complex containing epoxy resin composition for semiconductor encapsulation
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The invention is an epoxy resin composition for sealing a semiconductor, including (A) an epoxy resin and (B) a clathrate complex. The clathrate complex is one of (b1) an aromatic carboxylic acid compound, and (b2) at least one imidazole compound represented by formula (II): wherein R2 represents a hydrogen atom, C1-C10 alkyl group, phenyl group, benzyl group or cyanoethyl group, and R3 to R5 represent a hydrogen atom, nitro group, halogen atom, C1-C20 alkyl group, phenyl group, benzyl group, hydroxymethyl group or C1-C20 acyl group. The composition has improved storage stability, retains flowability when sealing, and achieves an effective curing rate applicable for sealing delicate semiconductors.
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- Novel 1,3,4-oxadiazole thioether derivatives targeting thymidylate synthase as dual anticancer/antimicrobial agents
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A series of novel 1,3,4-oxadiazole thioether derivatives (compounds 9-44) were designed and synthesized as potential inhibitors of thymidylate synthase (TS) and as anticancer agents. The in vitro anticancer activities of these compounds were evaluated against three cancer cell lines by the MTT method. Among all the designed compounds, compound 18 bearing a nitro substituent exhibited more potent in vitro anticancer activities with IC50 values of 0.7 ± 0.2, 30.0 ± 1.2, 18.3 ± 1.4 μM, respectively, which was superior to the positive control. In the further study, it was identified as the most potent inhibitor against two kinds of TS protein (for human TS and Escherichia coli TS, IC50 values: 0.62 and 0.47 μM, respectively) in the TS inhibition assay in vitro and the most potent antibacterial agents with MIC (minimum inhibitory concentrations) of 1.56-3.13 μg/mL against the tested four bacterial strains. Molecular docking and 3D-QSAR study supported that compound 18 can be selected as dual antitumor/antibacterial candidate in the future study.
- Du, Qian-Ru,Li, Dong-Dong,Pi, Ya-Zhou,Li, Jing-Ran,Sun, Jian,Fang, Fei,Zhong, Wei-Qing,Gong, Hai-Bin,Zhu, Hai-Liang
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p. 2286 - 2297
(2013/05/09)
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- Regioselective nitration of deactivated mono-substituted benzenes using acyl nitrates over reusable acidic zeolite catalysts
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Nitration of benzonitrile was investigated using a nitric acid/acid anhydride/zeolite catalyst system under different reaction conditions. Trifluoroacetic and chloroacetic anhydrides were found to be the most active among the anhydrides tried. Also, zeolites Hβ and Fe3+β (Si/ Al = 12.5) were found to be the most active catalysts. For example, nitration of benzonitrile with trifluoroacetyl nitrate under reflux conditions in dichloromethane gave 3- and 4-nitrobenzonitriles in quantitative yield, of which the para-isomer represented 24-28%. The yield of para-isomer was improved to 33% when passivated Hβ was used under similar reaction conditions. This is easily the most para-selective nitration of benzonitrile ever recorded. Also, no ortho-isomer was formed under the conditions tried. The zeolite can be easily recovered, regenerated by heating and reused up to six times to give results similar to those obtained with a fresh sample of the catalyst. The nitration system was applied successfully to a range of deactivated mono-substituted benzenes to give para-isomers in significantly higher proportions than in the corresponding traditional nitration reactions.
- Smith, Keith,Ajarim, Mansour D.,El-Hiti, Gamal A.
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experimental part
p. 270 - 278
(2010/12/19)
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- Influence of solvent on the ortho substituent effect in the alkaline hydrolysis of phenyl esters of substituted benzoic acids
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The second-order rate constants k (dm3mol-1 s -1) for the alkaline hydrolysis of phenyl esters of meta-, para-and ortho-substituted benzoic acids in aqueous 5.3 M NaClO4 and 1.0 M Bu4NBr were measured by UV/Vis spectrophotometry at 25 °C. The variations in the ortho inductive, ortho resonance, as well as meta and para polar effects with solvent parameters were studied using data for the alkaline hydrolysis of phenyl esters of substituted benzoic acids in various media. The dependence of the ortho substituent effect on solvent can be precisely described with the following equation: δlog kortho = log k ortho - log kH = 0.059 + 2.19σ1 +0.304σ°R + 2.79EBs -0.016 δEσ1-0.085δEσ°R, where δE is the solvent electrophilicity, δE = ES-E H2O, characterizing the hydrogen-bond donating power of the solvent. The increase in the meta and para polar substituent effects with decrease in the solvent hydrogen-bond donor capacity (electrophilicity) was approximately to the same extent (-0.068δEσ°m, p) as the resonance term for the ortho substituents. The steric term of ortho substituents was independent of the solvent parameters. The variations in the ortho inductive, ortho resonance, as well as meta and para polar substituent effects with the solvent electrophilicity were to the same extent as in phenyl benzoates containing the substituents in the phenyl part. The substituent effects in the alkaline hydrolysis of ethyl benzoates appeared to vary with the solvent electrophilicity nearly to the same extent as in the alkaline hydrolysis of substituted phenyl esters of benzoic acids. Copyright 2009 John Wiley Sons, Ltd.
- Nummert, Vilve,Piirsalu, Mare,Koppel, Ilmar A.
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experimental part
p. 497 - 504
(2011/08/08)
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- Alkoxycarbonylation of aryl iodides catalyzed by Pd with a thiourea type ligand under balloon pressure of CO
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Palladium-catalyzed alkoxycarbonylation of aryl iodides with a thiourea-oxazoline type ligand has been achieved under mild conditions. Various functional groups were tolerated and the yields were from moderate to excellent.
- Liu, Jing,Liang, Bo,Shu, Dongxu,Hu, Yanhe,Yang, Zhen,Lei, Aiwen
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p. 9581 - 9584
(2008/12/22)
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- Synthesis and?antimicrobial studies of?a?new series of?2-{4-[2-(5-ethylpyridin-2-yl)ethoxy]phenyl}-5-substituted-1,3,4-oxadiazoles
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A series of novel 2-{4-[2-(5-ethylpyridin-2-yl)ethoxy]phenyl}-5-substituted-1,3,4-oxadiazoles were synthesized by the oxidative cyclisation of hydrazones derived from 4-[2-(5-ethylpyridin-2-yl)ethoxy]benzaldehyde and aroylhydrazines using chloramine-T as oxidant. IR, NMR and elemental analysis characterized the newly synthesized compounds. The synthesized compounds were evaluated for their antimicrobial activity and were compared with standard drugs. The compounds demonstrated potent to weak antimicrobial activity. Out of the compounds studied, compounds 8c and 8d showed significant inhibition. Compounds 8b, 8f, 8k and 8e showed moderate activity. The minimum inhibitory concentration of the compounds was in the range of 8-26 μg ml-1 against bacteria and 8-24 μg ml-1 against fungi. The title compounds represent a novel class of potent antimicrobial agents.
- Gaonkar,Rai,Prabhuswamy
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p. 841 - 846
(2007/10/03)
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- Nitration of aromatic compounds by Zn(NO3)2· 2N2O4 and its charcoal-supported system
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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
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p. 263 - 270
(2007/10/03)
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- Relative reactivity of methyl iodide to ethyl iodide in nucleophilic substitution reactions in acetonitrile and partial desolvation accompanying activation
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Through the examination of empirical correlations involving activation parameters for nucleophilic substitution of methyl iodide and of ethyl iodide, nucleophiles have been classified into three series: (1) nucleophiles with two equivalent reaction sites, (2) nucleophiles with a chlorine atom in the para-position, and (3) nucleophiles with a single reaction site. Three types of partial desolvation processes accompanying activation have been deduced on the basis of these classifications. A major factor determining the relative reactivity of methyl iodide to ethyl iodide in the substitution reaction of an anionic nucleophile having a single reaction site in acetonitrile (kMeI/kEtI) is suggested to be partial desolvation around the nucleophilic center on going from reactant to transition-state.
- Kondo, Yasuhiko,Urade, Miyuki,Yamanishi, Yukari,Chen, Xinyu
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p. 1449 - 1454
(2007/10/03)
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- An improved method for the esterification of aromatic acids with ethanol and methanol
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A mixed catalyst Fe2(SO4)3·xH2O/ concentrated H2SO4 has been used to catalyze the esterification of aromatic acids with ethanol and methanol. This catalyst system is found to be effective for the rapid reactions and the esterification yields are excellent.
- Xu,Liu,Chen,Ma
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p. 2113 - 2117
(2007/10/03)
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- Synthesis and structure-activity relationship of diarylamide derivatives as selective inhibitors of the proliferation of human coronary artery smooth muscle cells
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A series of diarylamide derivatives were synthesized and evaluated for their inhibitory activities against human coronary artery smooth muscle cells (SMCs) and human coronary artery endothelial cells (ECs). Compound 2w was superior to the lead compound, Tranilast, in terms of the potency of the activity and cell selectivity.
- Gita, Haruhisa,Sobe, Yoshiaki,Akaku, Haruo,Ekine, Rena,Oto, Yuso,Isawa, Satoru,Hayashi, Hideya
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p. 549 - 551
(2007/10/03)
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- Chemistry of superacids: 35. * NO2Cl-3MXN systems: Superelectrophilic aprotic nitrating agents for deactivated aromatics
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Superelectrophilic nitration of deactivated aromatics with NO2Cl-3MXn complexes in aprotic nonpolar solvents such as CH2Cl2 makes it possible to obtain the corresponding nitro derivatives in good to almost quantitative yields under mild conditions.
- Olah,Orlinkov,Ramaiah,Oxyzoglou,Prakash
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p. 924 - 927
(2007/10/03)
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- An efficient general method for esterification of aromatic carboxylic acids
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Treatment of a variety of aromatic carboxylic acids with alcohols in the presence of thionyl chloride results in excellent yields of corresponding esters. This esterification system is compatible with a wide assortment of functional groups.
- Hosangadi, Bhaskar D.,Dave, Rajesh H.
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p. 6375 - 6378
(2007/10/03)
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- Process for the preparation of alkyl nitrobenzoates
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A process for the preparation of alkyl (C1 -C3) nitrobenzoates by reacting the nitrobenzoic acid to be esterified with an excess of about 300 to about 600 mol % of an alkanol (C1 -C3) in a solvent which is inert towards the starting compounds and the reaction product in the presence of a polyfluoroalkanesulfonic acid of the general formula (1) in which Y is a hydrogen or fluorine atom, with the proviso that, if Y is H, this hydrogen atom is in the β-position relative to the sulfo group, or the hydrate thereof as catalyst in an amount of about 0.1 to about 20 mol %, relative to the nitrobenzoic acid used, at temperatures from about 60° to about 120° C.
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- Sodium Hydrogen Telluride - A Mild Reagent for Deacylation of Aryl Acetates and Benzoates
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Sodium hydrogen telluride is found to be a mild and effective reagent for the deacylation of aryl acetates and benzoates.
- Shobana, N.,Shanmugam, P.
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- REARRANGEMENT OF SUBSTITUTED AROMATIC ACETALS CATALYSED BY γ-ALUMINA
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Aromatic acetals over γ-alumina undergo rearrangement to give the corresponding esters (b) and ethers (c) in good yield.The product distribution varied unusually over the range of reaction temperatures.The effect of substituents has also been felt much in the study.Probable mechanisms have been suggested for the reaction.The catalyst has been characterized by various studies and the specific poisoning of the catalyst has been done with NH3, CO2 and H2S.
- Xavier, N.,Arulraj, S. J.
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p. 2875 - 2878
(2007/10/02)
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