CH363332A - Process for the production of epoxy-ethylbenzenes - Google Patents

Description

  

  
 



  Process for the production of epoxy-ethylbenzenes
It is known that 1,3,5-triepoxyethylbenzene can be obtained by chlorinating triacetylbenzene, reducing the trichloroacetyl compound to 1,3,3,5-tri- (α-hydroxy-ss- chloro-ethyl) -benzene and splitting off chlorine water - to produce substance from the latter compound.



  Lithium aluminum chloride has hitherto been proposed as a reducing agent for the reduction of 1,3,5-trichloroacetylbenzene [H. Hopff and P.



  Jaeger, Helv. Chim. Acta, Vol. XL, p. 274 (1957)].



  This reducing agent is technically not usable because of its high price.



   It has now been found that the reduction of chloroacetylbenzenes to the corresponding chlorohydrins can also be carried out smoothly with aluminum isopropoxide according to Meerwein-Ponndorff with good yield. The splitting off of hydrogen chloride to form the epoxide can then take place in a known manner by treatment with alkali lye in an aqueous or alcoholic solution.



   example
120 parts of 1,3,5-trichloroacetylbenzene are dissolved in 250 parts of dioxane and mixed with 1000 parts of anhydrous isopropyl alcohol. 252 parts of aluminum isopropoxide are then added with stirring and the entire mixture is refluxed for 1H2 hour. In the process, all of the aluminum propyrate goes into solution.



  After boiling for 3 hours, the isopropyl alcohol and acetone mixture is distilled off. 100 parts of water are added to the distillation residue, and the aluminum hydroxide precipitate is filtered off and washed with acetone. After evaporation of the acetone, 117 parts of 1,3,5-tri- (a-hydroxy-β-chloroethylbenzene are obtained as a yellowish oil, which corresponds to a yield of 95 ovo. On dilution with ether and cooling, the pure trichlorohydrin crystallizes from a melting point of 120 to 122 C. It is processed further to give triepoxide by treatment with alkali lye in an aqueous solution.



   If in the above process, instead of 1,3,5-trichloroacetylbenzene, one starts from monochloroacetylbenzene or from 1,3- or 1,4-dichloroacetylbenzene and otherwise proceeds in the same way, then one obtains epoxyethylbenzene or the 1, 3- or 1,4-Di (epoxy-ethyl) -benzene also in good yield.



   PATENT CLAIM
Process for the preparation of epoxyethylbenzenes, characterized in that chloroacetylbenzenes are reduced with aluminum isopropylate and the chlorohydrins obtained are converted into epoxides by treatment with alkalis.

** WARNING ** End of DESC field could overlap beginning of CLMS **.



   

 

Claims (1)

** WARNING ** Beginning of CLMS field could overlap end of DESC **. Process for the production of epoxy-ethylbenzenes It is known that 1,3,5-triepoxyethylbenzene can be obtained by chlorinating triacetylbenzene, reducing the trichloroacetyl compound to 1,3,3,5-tri- (α-hydroxy-ss- chloro-ethyl) -benzene and splitting off chlorine water - to produce substance from the latter compound. Lithium aluminum chloride has hitherto been proposed as a reducing agent for the reduction of 1,3,5-trichloroacetylbenzene [H. Hopff and P. Jaeger, Helv. Chim. Acta, Vol. XL, p. 274 (1957)]. This reducing agent is technically not usable because of its high price. It has now been found that the reduction of chloroacetylbenzenes to the corresponding chlorohydrins can also be carried out smoothly with aluminum isopropoxide according to Meerwein-Ponndorff with good yield. The splitting off of hydrogen chloride to form the epoxide can then take place in a known manner by treatment with alkali lye in an aqueous or alcoholic solution. example 120 parts of 1,3,5-trichloroacetylbenzene are dissolved in 250 parts of dioxane and mixed with 1000 parts of anhydrous isopropyl alcohol. 252 parts of aluminum isopropoxide are then added with stirring and the entire mixture is refluxed for 1H2 hour. In the process, all of the aluminum propyrate goes into solution. After boiling for 3 hours, the isopropyl alcohol and acetone mixture is distilled off. 100 parts of water are added to the distillation residue, and the aluminum hydroxide precipitate is filtered off and washed with acetone. After evaporation of the acetone, 117 parts of 1,3,5-tri- (a-hydroxy-β-chloroethylbenzene are obtained as a yellowish oil, which corresponds to a yield of 95 ovo. On dilution with ether and cooling, the pure trichlorohydrin crystallizes from a melting point of 120 to 122 C. It is processed further to give triepoxide by treatment with alkali lye in an aqueous solution. If in the above process, instead of 1,3,5-trichloroacetylbenzene, one starts from monochloroacetylbenzene or from 1,3- or 1,4-dichloroacetylbenzene and otherwise proceeds in the same way, then one obtains epoxyethylbenzene or the 1, 3- or 1, 4-di (epoxy ethyl) benzene also in good yield. PATENT CLAIM Process for the preparation of epoxyethylbenzenes, characterized in that chloroacetylbenzenes are reduced with aluminum isopropylate and the chlorohydrins obtained are converted into epoxides by treatment with alkalis.