Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
  • C07C49/04—Saturated compounds containing keto groups bound to acyclic carbon atoms
  • C07C49/16—Saturated compounds containing keto groups bound to acyclic carbon atoms containing halogen
  • C07C49/167—Saturated compounds containing keto groups bound to acyclic carbon atoms containing halogen containing only fluorine as halogen
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
  • C07C51/58—Preparation of carboxylic acid halides
  • C07C51/62—Preparation of carboxylic acid halides by reactions not involving the carboxylic acid halide group
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2527/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • C07C2527/06—Halogens; Compounds thereof
  • C07C2527/08—Halides
  • C07C2527/12—Fluorides

Definitions

• the invention relates to a process for preparing compounds having a perfluoroalkylcarbonyl group by addition of carbonyl fluoride or carboxylic acid fluorides onto perfluoroalkenes.
• Fluorinated carbonyl compounds are intermediates in chemical synthesis.
• Perfluoroalkyl ketones and perfluoroalkyl alkyl ketones can be used, for example, as fire extinguishing media, see WO 01/05468.
• Fluorinated carboxylic acid fluorides are likewise intermediates in chemical synthesis, for example in the preparation of ketones, carboxylic acids or carboxylic acid derivatives such as esters or amides.
• carbonyl fluoride or fluorinated carboxylic acid fluorides such as trifluoroacetyl fluoride, n- perfluoropropionyl fluoride, i-perfluoropropionyl fluoride or ⁇ -H- octafluorobutyryl fluoride onto tetrafluoroethylene, hexafluoropropene or octafluorobutene.
• Caesium fluoride, potassium fluoride or potassium bifluoride are mentioned as catalysts.
• the reaction is carried out under autogenous pressure.
• the process of the invention provides for perfluorinated carboxylic acid fluorides and fluorinated ketones having a perfluoroalkyl group to be prepared by addition of carbonyl fluoride or carboxylic acid fluorides onto perfluorinated alkenes, wherein the addition step is carried pressureless in an aprotic solvent. Hence, the reaction is performed in the liquid phase.
• the addition of carboxylic acid fluorides onto perfiuorinated alkenes gives ketones.
• appropriate choice of the molar ratio of alkene to carbonyl fluoride allows the carbonyl fluoride to be added onto two molecules of the alkene to form ketones.
• the ideal stoichiometry according to the reaction equation for this reaction is 2:1. At an appropriate molar ratio, carbonyl fluoride and alkene form carboxylic acid fluorides. The ideal stoichiometry according to the reaction equation for this reaction is 1:1. The preparation of ketones from alkene and carboxylic acid fluoride is preferred for the purposes of the present invention.
• alkenes and acid fluorides with a boiling point of 80 0 C or less at a pressure of 1 bar (abs.), preferably less than 50 0 C at a pressesure of 1 bar (abs.) are applied. Very preferably, they have a boiling point of less than 26°C at 1 bar (abs.).
• R 1 and R 2 are identical or different and are each perfiuorinated Cl-C4-alkyl or fluorine.
• R 1 is preferably fluorine, perfluoromethyl or perfluoroethyl and R 2 is preferably fluorine, perfluoromethyl or perfluoroethyl.
• the perfiuorinated alkene is very particularly preferably hexafluoropropene.
• Preferred carboxylic acid fluorides are those of the formula R 3 -C(O)F (II), where R 3 is a Cl-C5-alkyl radical which may, if desired, be substituted by at least one halogen atom.
• R 3 is preferably Cl -C3-alkyl which is substituted by at least one fluorine atom.
• R 3 is very particularly preferably CF 3 , CHF 2 or CF 2 Cl.
• the process of the invention is outstandingly suitable for preparing trifluoromethyl perfluoroisopropyl ketone from trifluoroacetyl fluoride and hexafluoropropene.
• the reaction is carried out in a polar aprotic solvent.
• a high dielectric constant is advantageous.
• Such solvents also have the ability to dissolve inorganic salts.
• Preferred solvents have a boiling point which is at least 50 0 C, preferably at least 70 0 C.
• Dialkylamides of the lower carboxylic or fatty acids e.g. dimethylformamide, dialkyl ethers, alkylene or polyalkylene glycols, liquid nitriles such as acetonitrile, propionitrile, butyronitrile, valeronitrile, benzonitrile, dinitriles, e.g. adiponitril, sulpholane and ionic liquids are very well suited.
• solvents with a boiling point of lower than 250 0 C are applied.
• the process of the invention is preferably carried out at a temperature of at least 50 0 C, particularly preferably of at least 70 0 C.
• the upper limit is variable and determined by the boiling point of the solvent.
• An upper limit of 170 0 C is preferred.
• the upper limit is 150 0 C, still more preferably, 120 0 C.
• the reactants can be introduced in very finely divided form into the solvent or the reaction mixture. This can, for example, be effected by introducing the reactants, particularly if they are gaseous, through a frit. Alternatively, a reactor with Raschig or Pall rings can be applied. In such a reactor, gas bubbles are diminuted, thus providing a higher surface for reaction.
• pressureless means that, apart from the pressure for conveying the compounds introduced, no pressure acts on the reaction mixture, including no autogenous pressure.
• the pressure is thus at least 0.9 bar (abs.).
• the pressure lies in the range from atmospheric pressure (about 1 bar abs.) to a maximum of 1.5 bar (abs.).
• catalyst use can be made of any catalyst known for that process.
• a fluoride preferably a quaternary ammonium fluoride or an alkali metal fluoride such as KF or CsF.
• the catalyst can be supported by a carrier.
• it is carrier- free (bulk).
• An advantage of this reaction system is, inter alia, a low corrosivity, i.e. the reaction can be carried out in glass despite the presence of a high fluoride concentration without visible etching of the glass occurring.
• the process is preferably carried out continuously.
• An advantage of the process of the invention is that it can be carried out continuously and no pressure apparatuses are required. Large amounts can therefore be prepared in standard apparatuses, as a result of which high capital costs are avoided.
• the continuous mode of operation increases the space-time yield significantly (compared to the examples from US3185734, by a factor of 7). Yield and selectivity are very good.
• Example 1 Preparation of trifluoromethyl perfluoroisopropyl ketone
• Example 3 Preparation of trifiuoromethyl perfluoroisopropyl ketone
• the total crude yield is 71 %.
• the example demonstrates that relatively large amounts of ketone can be prepared in standard apparatuses and high capital costs for special reactors can thus be avoided.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Priority Applications (1)

Applications Claiming Priority (3)

Publications (1)

Family

ID=36273341

Family Applications (2)

Family Applications Before (1)

Country Status (4)

Families Citing this family (7)

Family Cites Families (3)

• 2005
  • 2005-12-30 EP EP05113084A patent/EP1803702A1/de not_active Withdrawn
• 2006
  • 2006-12-22 EP EP06830825A patent/EP1973864A1/de not_active Withdrawn
  • 2006-12-22 WO PCT/EP2006/070192 patent/WO2007077174A1/en active Application Filing
  • 2006-12-22 KR KR1020087018869A patent/KR20080085071A/ko not_active Application Discontinuation
  • 2006-12-22 CN CNA2006800535645A patent/CN101389585A/zh active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events