Abstract:
Enolate salts of 4-fluoro-2-hydroxymethylene-3-oxobutyrates of formula wherein R1 is C1-10 alkyl, R2 and R3 are independently hydrogen or fluorine, M is an alkali or alkaline earth metal, and n is 1 or 2, are prepared from enolate salts of the corresponding 4-fluoro-3-oxobutyrates and carbon monoxide. The enolate salts of formula I can be alkylated or acylated to obtain the corresponding enol ethers and esters. The 4-fluoro-3-oxobutyrate starting material can be prepared from 1,1-difluoroethyl methyl ethers by SbF5-catalyzed fluoromethane elimination followed by halogen exchange with lithium chloride, reacting the thus obtained fluoroacetyl chloride with ketene and quenching with the appropriate alcohol R1-OH.
Abstract:
Gasgemische, die HF, HCI oder HBr und andere Bestandteile enthalten, insbesondere solche Gasgemische, die Carbonsäurefluoride, C(0)F 2 oder Phosphorpentafluorid sowie HCI und gegebenenfalls HF enthalten, können mittels ionischer Flüssigkeiten aufgetrennt werden.
Abstract:
The invention pertains to a process for preparing chlorodifluoroacetyl fluoride (CDAF) by oxidation of chlorotrifluoroethylene (CTFE) in a solvent using a continuously stirred tank reactor. It provides a process for the production of chlorodifluoroacetyl fluoride by comprises reacting a solvent solution of chlorotrifluoroethylene with oxygen in a reactor to form a product which comprises chlorodifluoroacetyl fluoride. The reacting may be conducted in a continuous or batch mode.
Abstract:
The invention concerns a method for preparing a hydrofluoroalkane which consists in reacting a precursor of hydrofluoroalkane with hydrogen fluoride in the presence of a catalyst comprising chromium (Cr) and another metal.
Abstract:
Organic compounds, e.g., fluoro-organic compounds such as fluorocarboxylic acids or carboxylic acid chlorides can contain small quantities of carboxylic acid fluorides, HF or hydrolysable fluoride. Corrosive fluorides or hydrofluoric acid are then formed during derivatization, e.g., esterification. The invention relates to a method for producing especially fluoro-organic compounds such as carboxylic acids, carboxylic acid chlorides and derivatives thereof, e.g., carboxylic acid esters, from carboxylic acid chlorides containing acid fluorides or hydrolysable fluoride as appropriate, and alcohols, using the catalytic effect of "onium" salts of carboxylic acids. The products are low in fluoride. Alternatively, an inorganic-oxidic sorbent is used. The method is particularly suitable for producing esters of trifluoroacetic acid, chlorodifluoroacetic acid and trifluoroacetoacetic acid and difluoroacetoacetic acid.
Abstract:
Organic compounds, e.g., fluoro-organic compounds such as fluorocarboxylic acids or carboxylic acid chlorides can contain small quantities of carboxylic acid fluorides, HF or hydrolysable fluoride. Corrosive fluorides or hydrofluoric acid are then formed during derivatization, e.g., esterification. The invention relates to a method for producing especially fluoro-organic compounds such as carboxylic acids, carboxylic acid chlorides and derivatives thereof, e.g., carboxylic acid esters, from carboxylic acid chlorides containing acid fluorides or hydrolysable fluoride as appropriate, and alcohols, using the catalytic effect of "onium" salts of carboxylic acids. The products are low in fluoride. Alternatively, an inorganic-oxidic sorbent is used. The method is particularly suitable for producing esters of trifluoroacetic acid, chlorodifluoroacetic acid and trifluoroacetoacetic acid and difluoroacetoacetic acid.
Abstract:
The invention relates to a method for the production of carboxylic acid fluorides of the formula RCFXC(O)F, wherein X designates F or Cl. Compounds of the formula RCFXCHFCl are reacted with oxygen by photochemical oxidation in the gaseous phase. This yields good quantities of highly selective carboxylic acid fluorides. It is preferable to work under sensitization with chlorine and light at a wavelength of lambda >/=280 nm. This makes it possible to work without the use of pressure. Glass apparatus may be covered with a protective coating so as to protect it against traces of hydrogen fluoride. To this end, for example, heat-shrinkable sleeves made of translucent hydrogen fluoride-resistant material may be used. Polytetrafluoroethylene, polyfluoropropylene or a mixture thereof are especially suitable for this purpose. This type of protection is also suited for other reactions, such as photo-induced fluoro-dediazonation in hydrogen fluoride/pyridine for the production of aromatic compounds fluorinated in the nucleus or the oxidation of CHCL2 groups for the production of carboxylic acid fluorides.
Abstract:
The present invention concerns a process and intermediates for the manufacture of difluoro acetyl chloride. The invention further concerns a process for the manufacture of an agrochemically or pharmaceutically active compound, which comprises the process and intermediate for the manufacture of difluoro acetyl chloride for the manufacture of difluoro acetyl chloride or its intermediate.