Method for producing acyl peroxides
The invention relates to a method for producing acyl peroxides. According to the method, an acyl compound is reacted with an organic hydroperoxide and a base, to generate a two-phase mixture. The pH of the two-phase mixture is adjusted to 6 to 13. The obtained organic phase is extracted with an aqueous solution of a base and the aqueous extract is recirculated to the reaction step. The method according to the invention allows the recirculation of unreacted hydroperoxide to the reaction step.
1. A process for preparing an acyl peroxide, comprising:
a) reacting an acyl compound, an organic hydroperoxide and an aqueous solution of a base to obtain a biphasic reaction mixture, said biphasic reaction mixture containing an aqueous phase and an organic phase,
b) adjusting the pH of the aqueous phase of the biphasic reaction mixture obtained in step a) to 6 to 13,
c) separating the biphasic mixture obtained in step b) into an aqueous phase and an organic phase,
d) extracting the organic phase obtained in step c) with an aqueous solution of a base to obtain an aqueous extract and
e) recycling the aqueous extract obtained in step d) into step a),
wherein said acyl compound is selected from the group consisting of an acid chloride, a carboxylic anhydride and a chloroformate.
2. The process of claim 1 , comprising adjusting said pH to 11 to 12.5.
3. The process of claim 1 , wherein said organic hydroperoxide and said acyl compound are present at a ratio in a range from 1.01 to 2.
4. The process of claim 1 , wherein said organic hydroperoxide and said acyl compound are present at a ratio in a range from 1.05 to 1.5.
5. The process of claim 1 , wherein the aqueous solution of a base in step d) is present at a concentration of more than 0.5 mol/l.
6. The process of claim 1 , wherein the aqueous solution of a base in step d) is present at a concentration of more than 2 mol/l.
7. The process of claim 1 , wherein the extraction in step d) comprises a countercurrent extraction.
8. The process of claim 1 , wherein said organic phase and said aqueous solution in step d) are in contact for less than 20 minutes.
9. The process of claim 1 , wherein said organic phase and said aqueous solution in step d) are in contact for less than 2 minutes.
10. The process of claim 1 , comprising extracting said organic phase in a centrifugal extractor.
11. The process of claim 1 , wherein the acyl compound is an acid chloride selected from the group consisting of an acetyl chloride, a propionyl chloride, a butyryl chloride, an isobutyryl chloride, a valeroyl chloride, a 2-methylbutyryl chloride, a pivaloyl chloride, a 2-methylpentanoyl chloride, a 2-ethylbutyryl chloride, a 2-ethylhexanoyl chloride, a nonanoyl chloride, a 2,4,4-trimethylpentanoyl chloride, a 3,5,5-trimethylhexanoyl chloride, a decanoyl chloride, a neodecanoyl chloride, a lauroyl chloride, a benzoyl chloride, a 2-methylbenzoyl chloride, a 4-methylbenzoyl chloride, a 4-chlorobenzoyl chloride, a 2,4-dichlorobenzoyl chloride and a naphthoyl chloride.
12. The process of claim 1 , wherein the acyl compound is a chloroformate selected from the group consisting of a methyl chloroformate, an ethyl chloroformate, a n-propyl chloroformate, an isopropyl chloroformate, a n-butyl chloroformate, a sec-butyl chloroformate, a 2-ethylhexyl chloroformate, an isotridecyl chloroformate, a myristyl chloroformate, a cetyl chloroformate, a stearyl chloroformate, a cyclohexyl chloroformate, a 4-tert-butylcyclohexyl chloroformate, a benzyl chloroformate and a 2-phenoxyethyl chloroformate.
13. The process of claim 1 , wherein the organic peroxide is selected from the group consisting of a tert-butyl hydroperoxide, a tert-amyl hydroperoxide, a 1,1,3,3-tetramethylbutyl hydroperoxide, a 2,5-dimethylhexane 2-5-dihydroperoxide, a 2-5-dimethyl-3-hexyne 2,5-dihydroperoxide, a p-menthane hydroperoxide, a pinane hydroperoxide, a tetralin hydroperoxide, a cumene hydroperoxide, a 4-tert-butylcumene hydroperoxide, a 1,3-diisopropylbenzene dihydroperoxide and a 1,4-diisopropylbenzene dihydroperoxide.