DE804567C - Process for the preparation of halocarboxylic acid halides - Google Patents

Description

Process for the preparation of halocarboxylic acid halides The preparation of carboxylic acid chlorides by reacting carboxylic acids with inorganic acid chlorides, z. B. thione chloride is known.

It has now been found that one can, surprisingly, halocarboxylic acid halides Easier is obtained if lactones, especially y- or 8-lactones, are expediently obtained in the presence of a catalyst, treated with non-metallic compounds that contain more than one reactive halogen atom in the molecule, especially those in which several halogen atoms with a non-metallic central atom directly are connected.

As lactones z. B. in question y-butyrolactone, e-valerolactone, 8-valerolactone, 8-caprolactone, 8-isocaprolactone, α- and; 9-angelicalactone, ß-propionlactone, Phthalide, coumarin, γ-croton lactone, etc., and substituted lactones, e.g. B. halogenated Lactones, such as x-chloro- or x-bromo-f-butyrolactone and their homologues.

As a non-metallic compound with more than one reactive Halogen atoms in the molecule are, for example, thionyl chloride or bromide, Phosphorus trichloride, phosphorus tribromide, phosphorus pentachloride and benzotrichloride, Benzal chloride, carbon tetrachloride, chloroform, bromoform, iodoform and others. Catalysts suitable for the reaction are, in particular, acidic agents, for example concentrated sulfuric acid, anhydrous zinc chloride or aluminum chloride, furthermore Zinc dust.

Those easily prepared by the above process Halocarboxylic acid halides are valuable intermediate products for the production of dyes, pharmaceuticals, Textile auxiliaries, etc.

The parts given in the examples below are parts by weight.

Example s 258 parts of y-butyrolactone are mixed with 10 parts of anhydrous Zinc chlorine is added, whereupon 393 parts of thionyl chloride are obtained at an internal temperature of 50 to 60 ° gradually flowing in slowly. The mixture is left to stand for some time and then subjects it to fractional distillation in vacuo. There will be 352 parts y-chlorobutyric acid chloride of bp "= 76 to 77 ^ obtained. Example e To a mixture of 344 parts of γ-butyrolactone and 2o parts of concentrated sulfuric acid are left gradually 525 parts of thionyl chloride at 6o to 70 ° flow in and hold the reaction mixture at this temperature until SO, evolution has ended. From the 362 parts of γ-chlorobutyric acid chloride (VZ = I183) are distilled in the reaction mixture Kp "= 70 to 72 ° above. Example 3 165 parts of x-bromo-y-butyrolactone are in one 10 parts of zinc chloride are added to the stirred vessel and the mixture is heated to 60 to 70 minutes; then lets to run in 131 parts of thionyl chloride with stirring over the course of about 8 hours. The solution is until the termination of the SO. -Development moved on. From the reaction mixture oc-bromochlorobutyric acid chloride is obtained in good yield by fractional distillation in vacuo from Kp "= 86 to 92". In an analogous manner, the x-chlorobutyrolactone is obtained oc-, y-dichlorobutyric acid chloride with a b.p. = 80 to 82 °.

Beispie14 In a mixture of 100 parts of butyrolactone and 5 parts Zinc chloride is carried with stirring at 150 to 17o ° 24o parts of phosphorus pentachloride and keeps the reaction mixture for a few hours at this temperature. Afterward it is distilled in vacuo, with 112 parts of y-chlorobutyric acid chloride (VZ = 1185) pass 20 mm Hg pressure at 76 to 78 ° J. Example s For a mixture of 86 parts Anhydrous butyrolactone and 5 parts of zinc chloride are gradually left to 195.5 Parts of benzotrichloride flow in and the mixture is heated to 16o for some time to 18o '. From the reaction solution is obtained by distillation in vacuo as well Benzoyl chloride in good yield γ-chlorobutyric acid chloride. Example 6 In one 86 parts of butyrolactone, 5 parts of zinc chloride and 154 parts of carbon tetrachloride are placed in the pressure vessel heated to 150 to 16o °. After relaxing the phosgene formed on a with sodium hydroxide solution, the reaction product is distilled in vacuo and receives γ-chlorobutyric acid chloride in good yield.

Claims (1)

Claim: Process for the preparation of halocarboxylic acid halides, characterized in that lactones, in particular γ- or δ-lactones, advantageously in the presence of catalysts, are treated with non-metallic compounds which contain more than one reactive halogen atom in the molecule.