Phase Transfer Catalysts

Phase Transfer Catalysts

    CatOnium phase transfer catalysts (PTC) are quaternary ammonium and phosphonium salts, which are widely used in the production of:

  • Additives
  • Monomers
  • phase transfer catalysts
  • Agrochemicals
  • Organic fine chemicals
  • Dyes
  • Pharmaceuticals
  • Explosives
  • Petrochemicals
  • Flavors
  • Resins
  • Fragrances
  • Rubber
  • Monomers
  • Surfactants
  • Paint & Coatings
  • Zeolite templates
  • In addition CatOnium Phase Transfer Catalysts are also used in polymer modifications and pollution treatment and the removal or destruction of impurities in
    wastes and product streams.

    Typical reactions where CatOnium phase transfer catalysts are employed include:

  • Aldol condensation
  • Dehydrohalogenation
  • N-, C-, and S-alkylation
  • Borohydride reduction
  • Etherification
  • Oxidation and epoxidation
  • Carbene reactions
  • Esterification and transesterification
  • Reduction
  • Carbonylation
  • Hydrohalogenation
  • Transition metal co-catalysis
  • Chloromethylation
  • Hydrogenation
  • Wittig reaction
  • Darzens condensation
  • Michael addition
  • Displacements reactions using:

  • Acyl halides
  • Bromides
  • Iodides
  • Alkyl halides
  • Cyanates
  • Phosphoro halides
  • Allyl chloride
  • Cyanides
  • Thiocyanates
  • Anhydrides
  • Epichlorohydrin
  • Sulfides
  • Aryl halides
  • Fluorides
  • Sulfonyl halides
  • Azides
  • Inorganic nucleophiles
  • Benefits
    The use of phase CatOnium phase transfer catalysts offers number of benefits from synthetic, economic, manufacturing and engineering point of view. This includes:

  • Easy and reliable up-scaling
  • Low investments costs
  • Elimination of expensive and dangerous reactants such as metal alkoxides
  • Mild reaction conditions with increased process reliability
  • Flexibility in solvent choice
  • Minimization of industrial waste
  • High yield and purity of the end
  • Reduced reaction time
  • Increased reaction rates that leads to enhanced selectivity
  • Reduction of side products output
  • Increased reactor volume efficiency
  • Reduction or even elimination of the use of organic solvents
  • Low energy consumption

  • Simplicity of the synthetic procedure
  • Most common CatOnium PTC’s are quaternary ammonium salts containing either alkyl or mixed alkyl/aryl groups. Their applicability is restricted by the thermal stability which is limited to about 100°C. CatOnium phase transfer catalysts comprises broad range of quaternary ammonium halides, with F,Cl,Br and I as counter anions, and limited number of quaternary hydroxyl ammonium compounds, with an OH group as counter anion.

    Phosphonium PTC’s are used in the cases in which the use of ammonium compounds is not suitable because of their thermal instability.
    The thermal stability of CatOnium quaternary phosphonium salts is quite good in a range between 120-150°C, with indications that they can be also used at temperatures up to 200 °C.