609-99-4Relevant articles and documents
Intramolecular base catalysed hydrolysis of ortho-hydroxyaryl esters: The anomalous position of methyl 3,5-dinitrosalicylate on the Linear Free Energy Relationship plot
Moozyckine, Alexei U.,Davies, D. Martin
, p. 1158 - 1161 (2002)
The pKa of the ortho-hydroxy group in methyl 3,5-dinitrosalicylate, HMDNS, is 2.45. Rate constants for the reaction of its conjugate base, MDNS- with hydroxide anion and water are 5.3 × 10-2 mol dm-3 s-1 and 6.6 × 10-6 s-1, respectively at 25°C. The rate constant for the uncatalysed reaction of HMDNS and water is 6.5 × 10-6 s-1 and so there is no evidence for intramolecular general base catalysis of the water reaction with MDNS- by the weakly basic ortho-O-. By means of Bronsted plots the water reaction of MDNS- is compared with that of a group of other salicylate esters (β = 0) and also a structurally different group of esters (β = 0.4), both of which undergo intramolecular base catalysed hydrolysis. Although the title ester structurally belongs to the first set of compounds, its anomalous position on the plot clearly corresponds to the trend of the second set. This is explained in terms of differences in resonance stabilisation and hydrogen bonding in the transition state.
NOVEL WATER SOLUBLE POLYIMIDE RESIN, ITS PREPARATION AND USE
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, (2011/08/03)
The present invention relates to a novel water soluble polyimide resin, which contains a hydrophilic functional group such as —OH, —COOH to increase the solubility of the polyimide resin in alkali aqueous solution, and is suitable for using as an insulation film in electronic and photoelectric products. The present invention also relates to preparation and use of the above polyimide.
INHIBITORS OF STEAROYL-COA DESATURASE
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, (2009/06/27)
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.
Process for the synthesis of hydroxy aromatic acids
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Page/Page column 20-21, (2008/06/13)
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.
Cold microwave chemistry: synthesis using pre-cooled reagents
Bose, Ajay K.,Ganguly, Subhendu N.,Manhas, Maghar S.,He, William,Speck, Jeffrey
, p. 3213 - 3215 (2007/10/03)
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.
Nitration of aromatic compounds by Zn(NO3)2· 2N2O4 and its charcoal-supported system
Iranpoor, Nasser,Firouzabadi, Habib,Heydari, Reza,Shiri, Morteza
, p. 263 - 270 (2007/10/03)
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.
Synthesis of salicylic acid derivatives from the corresponding 2-chlorobenzoic acid using water as solvent
Pellon Comdom, Rolando F.,Docampo Palacios, Maite L.
, p. 2055 - 2059 (2007/10/03)
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.
Pseudopolymorphs of 3,5-dinitrosalicylic acid
Kumar, V. S. Senthil,Kuduva, Srinivasan S.,Desiraju, Gautam R.
, p. 1069 - 1073 (2007/10/03)
Seven pseudopolymorphs of 3,5-dinitrosalicylic acid are studied. Four of these (A-D) are obtained from dioxane and their formation is rationalised on the basis of simultaneous O-H ... O and C-H ... O bond formation between the donor-rich solute molecule a
Micellar ctalysis of organic reactions. XXXVIII:. A study of the catalytic effect of micelles of 3-hydroxymethyl-1-tetradecylpyridinium bromide on amide hydrolysis and nucleophilic aromatic substitution
Broxton, Trevor J.
, p. 541 - 543 (2007/10/03)
The preparation of 3-hydroxymethyl-1-tetradecylpyridinium bromide and its use as a catalyst of nucleophilic aromatic substitution and also amide hydrolysis are reported. It was found that the hydroxydehalogenation of nitro-activated aryl halides was much faster in these micelles than in the presence of cetyl(2-hydroxyethyl)dimethylammonium bromide. It was concluded that the increased catalysis of nucleophilic aromatic substitution by this micelle was due to a faster decomposition of the aryl micellar ether which must occur before the phenolate product is released. No such difference in the two micelles was found for amide or thioamide hydrolysis since in these reactions the product amine is produced in the first step of the reaction and decomposition of the acylated micelle is not required in the rate-determining step of the reaction.
The Effects of Single- and Twin-Tailed Ionic Surfactants on the Hydroxy- dehalogenation of Charged Substrates
Cipiciani, Antonio,Primieri, Stefania
, p. 1505 - 1509 (2007/10/02)
Reactions of OH- with 4-chloro-3,5-dinitrobenzoic and 2-chloro-3,5-dinitrobenzoic acids have been examined in solutions of cetyltrimethylammonium chloride, bromide and hydroxide, bis(dodecyl)dimethylammonium chloride, and bis(tetradecyl)dimethylammonium chloride.Rate effects were analysed quantitatively in terms of the distribution of reactants between water and the colloidal particles.It has been found that twin-tailed ionic surfactants better distinguish between favourable and unfavourable orientations of substrate molecules within micellar aggregates than do single-tailed ionic surfactants.
