35535-81-0Relevant articles and documents
Synthesis of enantiomerically pure 3-aryloxy-2-hydroxypropanoic acids, intermediate products in the synthesis of cis-4-Aminochroman-3-ols
Bredikhina,Pashagin,Kurenkov,Bredikhin
, p. 535 - 539 (2014/06/10)
Oxidation of accessible (R)-3-chloropropane-1,2-diol to (R)-3-chloro-2-hydroxypropanoic acid and subsequent reaction of the latter with ortho-substituted sodium phenoxide gave a number of enantiomerically pure 3-aryloxy-2-hydroxypropanoic acid which are intermediate products in the synthesis of nonracemic 4-aminochroman-3-ols.
UV-Vis Spectrophotometric Determination of the Dissociation Constants for Monochlorophenols in Aqueous Solution at Elevated Temperatures
Uchida, Miho,Okuwaki, Akitsugu
, p. 19 - 39 (2007/10/03)
The dissociation constants of monochlorophenols (2-, 3-, 4-chlorophenols) were examined using direct UV-vis spectroscopy at temperatures from 25 to 175°C and at saturated vapor pressures in a high-temperature, high-pressure cell. The dissociation constant, Ka increased under experimental temperatures in the order: 2-chlorophenol, 3-chlorophenol, and 4-chlorophenol. The dissociation constant of 4-chlorophenol increased with increasing temperature under experimental conditions, while those of 2-and 3-chlorophenol reached maximum values at around 125°C, and then decreased with further increases in temperature. The slope of ?(log K)/? (1/T) was nonconstant and positive, that is, endothermic, below 150°C. The data on dissociation constants were analyzed by simultaneous regression to yield a five-term equation that described the Van't Hoff isobar. The magnitude of enthalpy ΔH increased at 25°C in the order: 3-chlorophenol, 4-chlorophenol, and 2-chlorophenol. The decrease in enthalpy at the absolute temperature was larger for 3-chlorophenol than for either 2- or 4-chlorophenol. Considering the equilibrium constant Kb for the isocoulombic reaction of monochlorophenol with OH-, the nearly linear relationship of log Kb vs. 1/T for temperatures between 25 and 175°C indicates that the ΔCp values for this isocoulombic reaction are low.
Process for the manufacture of anhydrous alkali metal arylate solutions and separation of the arylates from alkali metal sulfite
-
, (2008/06/13)
Anhydrous organic solutions of alkali metal arylates are prepared by dissolving an alkali metal arylate or reacting an arylhydroxy compound with alkali metal hydroxide in a ketone immiscible or incompletely miscible with water at room temperature and removing the water from the solution, if any, by azeotropic distillation with reflux.
Alkyl esters of 4-chlorophenoxy-4-oxo-cycloalkyl-carboxylic acid
-
, (2008/06/13)
Tricyclic compounds of the formula SPC1 Wherein R1 is hydrogen, halogen, lower alkyl, lower alkoxy, lower alkylthio, trifluoromethyl, cyano, carbamoyl, carboxy, lower alkoxy carbonyl, nitro, amino, mono-lower alkylamino, di-lower alkylamino, acyl, acylamido, sulfamoyl, di-lower alkylsulfamoyl, or difluoromethylsulfonyl; R2 is hydrogen, lower alkyl, amino-lower alkyl, mono-lower alkyl-amino-lower alkyl, or di-lower alkylamino-lower alkyl; n and r are independently 1 or 2; and X is oxygen or sulfur, prepared, inter alia, from the correspondingly substituted phenol or thiophenol and haloketocyclohexane or pentane carboxylic acid ester, are described. The end products are useful as anti-inflammatory and anti-rheumatic agents.
