SU95525A1 - Method for producing phenylacetic acid - Google Patents

Description

A known method for the preparation of phenylacetic acid from benzyl chloride, which, in reaction with potassium cyanide, forms a benzyl cyapide; saponification of the latter gives phenylacetic acid.

The disadvantage of this method is the use of highly toxic potassium potassium.

The proposed method does not require the addition of n, potassium ananil, is simpler and makes it possible to use chloroacetophenone as the starting material.

The peculiarity of the proposed method CvJ-CTOHT is that ififbiii is dissolved in luiepTioM organic-m solvent x.-

Examples: 1. 6.4 g of x.toraceto (|)) per) are dissolved in 60 ml of dry ether. When the mixture is not mixed, it is introduced into the receptacle |) in small portions of 3.8 i powdered caustic potash. The resulting reaction mixture is boiled under stirring for one hour, after which it is cooled and cold water is added to the drinks in small portions. The ether solution is washed with a dilute alkali solution, and the alkaline extract is then attached to the aqueous layer. The latter is heated with resin that has accumulated on the bottom of the flask, and then hot. The solution is decanted from the wet residue, which is additionally extracted with water. The combined aqueous extracts are acidified with a Congo-concentrated hydrochloric acid with hydrochloric acid, and the precipitated phenylacetic acid is salted out and repeatedly removed by ether. The ether extract is dried over anhydrous sodium sulfate, the ether is distilled off, and the residue is distilled in vacuo. 4.75 g (84% of the theoretical yield) of those n-1 cc 1 phenyl acetic acid with a temperature of 67–70 ° C is obtained. After recrystallization from water, the acid has a melting point of 75 ° -76 ° and does not give a depression with an acid-shaped feiyl-freeze.

2. A solution of 6.4 g of chloroacetophenone in 60 ml of absolute benzene is treated with 3.8 g of powdered

jYo 95525 -2 -

caustic potash, as in example I. Pro-solvent preparations and distillation in

duration: 3,32 g (57% of the theoretical case is 30 minutes) are obtained in this vacuum. The resultant technical product is sucked off and rinsed with milicussic acid,

repeatedly benzol m. Benzene „

solution, then exhaustively extract-Subject and revision and and

a cabin with a saturated solution of the two-preparation method {) enylacetic

carbon dioxide soda. Soda extract,., Exc and chaa and ys,

they are filtered from a precipitate, that is dissolved in ether or a benzoic filter, filtered, acidified and the chloroacetophenone removed from the sol is treated

cabin benzene. As a result of drying, mink-borne caustic potash.