摘要:
Mono- and bis-hypofluorites respectively of formula: FO₂S-R f -CF₂OF and FOCF₂-Rʹ f -CF₂OF wherein R f is perfluoroalkylene or perfluorochloroalkylene and Rʹ f is perfluoroalkylene or perfluorooxyalkylene are prepared by a process which is conducted continuously, at a temperature from 0 to 60°C and comprises starting from the respective acyl fluorides by reaction of fluorine in the gas phase in the presence of a catalyst consisting of K, Rb, Cs or Ba fluorine, preferably supported on a metal material.
摘要:
Fluoroxy-halo-compounds are prepared by direct reaction between fluorine and organic compounds having a molecular structure in which at least one oxygen atom is directly bound to a carbon atom in the carbonylic form, in the presence of a fluorination catalyst, in a gaseous phase, at an absolute pressure of between 50 and 800 kPa and at a temperature higher than -50°C and up to 250°C, under conditions of continuous feeding of the reactants and a continuous removal of the reaction product.
摘要:
Fluoroxy-halo-compounds are prepared by direct reaction between fluorine and organic compounds having a molecular structure in which at least one oxygen atom is directly bound to a carbon atom in the carbonylic form, in the presence of a fluorination catalyst, in a gaseous phase, at an absolute pressure of between 50 and 800 kPa and at a temperature higher than -50°C and up to 250°C, under conditions of continuous feeding of the reactants and a continuous removal of the reaction product.
摘要:
Process for the preparation of chloro-oxy-halo-compounds by means of the direct reaction between FCl and organic compounds having a molecular structure wherein an oxygen atom is directly linked to a carbon atom in the carbonyl form, in the presence of a catalyst constituted by an alkali metal or alkali-earth metal fluoride, preferably selected from K, Rb, Cs, Ba, Sr, the reaction being carried out continuously in the gas phase.
摘要:
The new compound bromofluoroethylhypofluorite, having the formula CF₂BrCF₂OF is obtained by starting from by the reaction in gaseous phase with fluorine, in the presence of a catalyst constituted by CsF on a support constituted by copper (or by another metal) in the form of a porous material having a surface area of at least 0.1m²/g.
摘要:
The invention relates to a use of a fluorination gas, wherein the elemental fluorine (F 2 ) is preferably present in a high concentration, for example, in a concentration of elemental fluorine (F 2 ), especially of equal to much higher than 15 % or even 20 % by volume (i.e., at least 15 % or even 20 % by volume), and to a process for the manufacture of a fluorinated benzene starting from benzoic acid by direct fluorination employing a fluorination gas, wherein the elemental fluorine (F 2 ) is preferably present in a high concentration, and subsequent decarboxylation of the benzoic acid hypofluorite obtained by direct fluorination. The process of the invention is also directed to the manufacture of a benzoic acid hypofluorite by direct fluorination of benzoic acid. Especially the invention is of interest in the preparation of fluorinatedbenzene, final products and as well intermediates, for usage in agro-, pharma-, electronics-, catalyst, solvent and other functional chemical applications. The fluorination process of the invention may be performed batch-wise or in a continuous manner. If the process of the invention is performed batch-wise, a column (tower) reactor may be used. If the process of the invention is continuous a micro reactor may be used. The invention is characterized in that the starting compound is benzoic acid, and the fluorinated compound produced is a benzoic acid hypofluorite obtained by direct fluorination, which benzoic acid hypofluorite can be converted by decarboxylation to a fluorinated benzene, preferably monofluorobenzene.
摘要:
The present invention relates to a continuous method for the preparation of (S)-2-acetyloxypropionic acid from an aqueous solution of lactic acid and acetic anhydride, in acetic acid. (S)-2-acetyloxypropionic acid is used for the preparation of (S)-2-acetyloxypropionic acid chloride, an essential intermediate compound for the preparation of lopamidol and has to be industrially produced with high purity and suitable quality for producing lopamidol according to the Pharmacopoeia requirements. The continuous process according to the invention, comprises therefore also the chlorination steps of (S)-2-acetyloxypropionic acid with thionyl chloride to give the corresponding (S)-2-acetyloxypropionic acid chloride which is further distilled to give the suitable purity characteristics for its use for the preparation of non-ionic iodinated contrast agents as lopamidol.