摘要:
Difluoroethanol is produced by hydrogenation, in the presence of an effective amount of a catalyst containing at least one element of Group VIII of the Periodic Table deposited onto a solid, acidic mineral support, of an acetyl halide having the following formula (I), in which formula X is a halogen atom other than a fluorine atom:
摘要:
The present invention relates to a method for preparing difluoracetonitrile and the derivatives thereof. The method for preparing difluoroacetonitrile according to the invention is characterized in that it includes reacting halogenodifluoromethane and a source of cyanide anions in an alkaline medium. The invention also relates to the use of difluoroacetonitrile as an intermediate in the manufacture of difluoroacetic acid and the salts, esters, or amide thereof.
摘要:
A method for preparing difluoroacetic acid is described. The method can include: reacting a difluoroacetic acid ester with an aliphatic carboxylic acid which, after transesterification, results in the formation of difluoroacetic acid and the corresponding carboxylic acid ester, the carboxylic acid being selected such that the ester of the carboxylic acid has a lower boiling point than that of difluoroacetic acid; and removing the ester of the carboxylic acid by distillation as the ester forms, thus enabling the difluoroacetic acid to be recovered.
摘要:
A method for preparing fluoroalkanesulphinic acid esters is described. The preparation of esters of trifluoromethanesulphinic acid, commonly referred to as “triflinic acid,” is also described. A method for preparing a fluoroalkanesulphinic acid ester is also described wherein the method includes reacting a fluoroalkanesulphinic acid with an organic carbonate leading to the formation of a fluoroalkanesulphinic acid ester and carbon dioxide, which is removed during the reaction.
摘要:
A process for the production of a compound of formula (III) which comprises a step of reacting a compound of formula (I) with an excess amount of a compound of formula (II) in absence of aromatic solvent, wherein n is 0, 1, 2, 3 or 4; X is NH, O or S; each R1 group may be the same or different, and is independently selected from the group consisting of hydrogen, hydroxyl, alkoxy, alkyl, carbonyl, carboxyl, carboxylic acid ester, amido, cyano, halogenated aliphatic, nitro, and amino; and R2 group is selected from the group consisting of hydroxyl, Cl, F, Br, amino, and alkoxy.
摘要:
The subject of the present invention is a method for separating a carboxylic acid in salified form bearing at least one halogen atom at the α position of the carbonyl group from a medium comprising it. The method according to the invention, for separating a carboxylic acid in salified form bearing at least one halogen atom at the α position of the carbonyl group from an aqueous medium comprising it, is characterized by the fact that the latter is brought into contact with an onium salt leading to the formation of two phases: an organic phase comprising the salt resulting from the reaction of the salt of the carboxylic acid bearing at least one halogen atom at the α position of the carbonyl group and of the onium salt leading to the displacement of the cation from the carboxylic acid by the onium, an aqueous phase comprising the various salts, in particular the one resulting from the reaction of the cation of the carboxylic acid with the anion of the onium, and by the fact that the organic and aqueous phases are then separated and that the onium salt of the carboxylic acid is recovered from the organic phase.
摘要:
The present invention relates to a method for preparing a highly pure trifluoromethanesulphinic acid. The method of the invention for preparing a highly pure trifluoromethanesulphinic acid, starting from an aqueous mixture comprising a trifluoromethanesulphinic acid salt, a trifluoroacetic acid salt and saline impurities resulting from the method for preparing same, is characterized in that said mixture is subjected to the following operations:- acidification such that the trifluoroacetic acid salt and the triflinic acid salt are released in an acid form,- separation of the trifluoroacetic acid and trifluoromethanesulphinic acid by distillation enabling the trifluoroacetic acid to be recovered at the top of the distillation and the trifluoromethanesulphinic acid to be recovered at the bottom of the distillation,- separation by distillation of the trifluoromethanesulphinic acid present in the distillation residue previously obtained.
摘要:
A method for preparing difluoroacetic acid esters is described. The method can include reacting difluoroacetyl fluorine with an aliphatic or cycloaliphatic alcohol in the presence of a heterogeneous mineral base.
摘要:
Difluoroethanol is produced by hydrogenation, in the presence of an effective amount of a catalyst containing at least one element of Group VIII of the Periodic Table deposited onto a solid, acidic mineral support, of an acetyl halide having the following formula (I), in which formula X is a halogen atom other than a fluorine atom:
摘要:
A method for preparing polyorganosiloxanes (POS) by a ring-opening polymerization and/or linear, non-linear or cyclic POS redistribution in the presence of a nucleophilic carbene. The initial efficiency of the POS conversion is substantially increased at low temperature, resulting in less residual content of initial POS.