Abstract: The invention relates to the preparation of glyoxylic acid by oxidizing an aqueous solution of glyoxal having a pH less than 1 with molecular oxygen in the presence of nitrogen monoxide as a catalyst.This process allows the practically total conversion of the starting glyoxal with a good yield of glyoxylic acid.

Abstract: The invention concerns a process for preparation of crystallized monohydrated sodium phenylpyruvate comprising: hot reacting benzaldehyde in an aqueous medium in the presence of a catalytic quantity of ethanolamine with the stoichiometric quantity of hydantoin, then treating the reactional medium hot at pH=14 through an excess of sodium hydroxide, acidifying to pH=9 with concentrated hydrochloric acid the so obtained solution and separating the formed precipitate.

Abstract: Pure crystalline racemic sodium parahydroxymandelate free from any ions of chloride, acetate, formate and sulfate group, is manufactured by condensing in water, in the presence of sodium hydroxide at a temperature between 30.degree. and 100.degree. C., glyoxylic acid or sodium glyoxylate with an excess of phenol, concentrating it hot, until the start of crystallization of the solution thus obtained after neutralization and removal of the unconverted phenol either by steam distillation, or by extraction with a water-immiscible organic solvent. The resulting suspension obtained is cooled, drained after some hours of standing at a temperature close to 5.degree. C., and the resulting precipitate recovered by washing it with iced water followed by drying to constant weight. The product is useful for the manufacture of crystalline sodium paraformylphenolate.

Abstract: Pure crystalline racemic sodium parahydroxymandelate free from any ions of chloride, acetate, formate and sulfate group, is manufactured by condensing in water, in the presence of sodium hydroxide at a temperature between 30.degree. and 100.degree. C., glyoxylic acid or sodium glyoxylate with an excess of phenol, concentrating it hot, until the start of crystallization of the solution thus obtained after neutralization and removal of the unconverted phenol either by steam distillation, or by extraction with a water-immiscible organic solvent. The resulting suspension obtained is cooled, drained after some hours of standing at a temperature close to 5.degree. C., and the resulting precipitate recovered by washing it with iced water followed by drying to constant weight. The product is useful for the manufacture of crystalline sodium paraformylphenolate.

Abstract: The invention relates to obtaining aromatic nitriles of general formula: (R).sub.n --C.sub.6 H.sub.4 --CN, where n=1, 2 or 3, and the rest R, identical or different represent an atom of hydrogen, chlorine or bromine or an alkyl, aryl, alkoxy, alkylamino, hydroxy or amino group, by a process comprising decarboxylating ammoxidation reaction, in an alkaline aqueous medium, at a pH higher than, or equal to, 13, in the presence of a catalyst based on one or several transition metals and an alkaline hydroxide, applied to an arylglyoxylic acid free or salified, of the formula: (R).sub.n --C.sub.6 H.sub.4 --CO--COOH (where n and R have the above-mentioned meanings), or to one of its functional derivatives of the lactone, lactame or C.sub.1 -C.sub.3 -alkyl ester type.

Abstract: The invention relates to a process for preparation of hydroxyarylglyoxylic acids starting from hydroxyarylglycolic acids, by catalytic oxidation in an aqueous alkaline medium to pH higher than, or equal to, 11.5, through oxygen or oxygen-containing gas, characterized in that it is carried out in homogeneous phase at a temperature lower than, or equal to, 30.degree. C., and in the presence of cupric ions, and in that at the end of the reaction, the desired acid is isolated from the reactional medium through acidification to pH of about 0.5.The sodium parahydroxyphenylglyoxylate is obtained when acidification is stopped at pH=5, at the end of the reaction.

Abstract: Sodium paraformylphenolate crystallized with two molecules of water is manufactured by:(a) condensing glyoxylic acid with an excess of phenol in water in the presence of sodium hydroxide at a temperature comprised between 30.degree. C. and 100.degree. C.;(b) neutralizing the solution thus obtained and then freeing it from the unconverted phenol by steam distillation or extraction with a water-immiscible organic solvent and then subjecting it hot under a pressure of oxygen, to a catalytic decarboxylating oxidizing degradation in the presence of sodium hydroxide;(c) allowing the aqueous solution so-obtained, after removal of the catalyst by filtration, and then concentration hot under vacuum to 60% plus or minus 10% of its initial volume, to crystallize; and(d) draining the precipitated crystals, washing them and then drying them to constant weight under vacuum of 1 mm of mercury at 20.degree. C.

Abstract: The invention relates to a process of preparation of racemic hydroxyarylglycolic acids and the novel products resulting therefrom.According to such process glyoxylic acid is condensed in water in the presence of an alkaline agent at a temperature of between 35.degree. and 100.degree. C., on an excess, or not, of phenolic aromative derivative other than phenol, having at least one proton on either of the ortho or para positions with respect to the phenol function.Application to the production of novel acids such as 4-hydroxy 3-tertiobutyl mandelic acid, 2-hydroxy 5-tertiobutyl mandelic acid, 3-chloro 4-hydroxy mandelic acid, 2-fluoro 4-hydroxy mandelic acid, monohydrated 3,5-dimethoxy 4-hydroxy mandelic acid, 2-hydroxy 5-methyl mandelic acid, (1-hydroxy 2-naphthyl) glycolic acid, 4-ethyl 2-hydroxy mandelic acid, and 4-hydroxy 3-methyl mandelic acid.

Abstract: Condensation of the addition product of glyoxylic acid and amides with hydroxyaryl compounds is effected by a first step, wherein the reaction is carried out hot, at a temperature below 60.degree. C, of an aliphatic amide having at the most 4 carbon atoms selected from the group of acetamide, chloracetamide, propionamide, acrylamide and butyramide, on an aqueous solution of glyoxylic acid. Then in a second step, after the addition of acetic acid and gaseous hydrochloric acid, condensation is effected at a temperature below 35.degree. C of the carboxamidoglycolic acid with an excess reaching 500% of hydroxyaryl compound selected from the group comprising phenol and its alkyl derivatives, their halogen derivatives, polyphenols and their ethers and betanaphthol. After the condensation of said second step, the volatile products are removed by vacuum distillation.

Abstract: This is an improved process of manufacturing N-acyl derivatives of glycines .alpha.-substituted by radicals with an aromatic nature by condensation of the addition product of glyoxylic acid and an amide, with an aromatic compound. In a first stage, the reaction is carried out at low temperature, in a concentrated sulfuric medium, of an aliphatic nitrile of the formula R--C.tbd.N in which R is a radical selected from the group of substituted and unsubstituted, saturated and unsaturated alkyl radicals, with a concentrated aqueous solution of glyoxylic acid. Then in a second stage, the mixture obtained is condensed also at low temperature with a compound of aromatic nature not including a hydroxyl group and having at least one substitutable free hydrogen, and the resulting product is collected. The concentrated sulfuric acid may be supplemented with acetic acid during the second stage. A surface active agent may be also added in this stage.