SU93037A1 - Method for preparing dichloroacetic acid esters - Google Patents

Description

-) dichloroacetic acid can be obtained .113 chlorine by means of izimodeystli d.lanpdaki c (fir-tree. metals or c, iol., -; - Iran is simpler and easier to implement.However, the formation of sharpening amounts of free cyanide Lodorium. Kpaiine makes it difficult to carry out the process, and the efficiency of this method of chloroacetic acid contains Scarfi, which does not allow them to be used in production e medication without sniffing.

1 (the edited method is different from the fact that in the cops process of the sylpushc acid is not 1 gral from the addition of formalin, and as a source of SIRLCHD the episode: d, sitit NR (use aldehyde or ketone as a source, i have a nd-i-ry, i have a ketone, i am i the ipt i have a i-th i-ketone. alcohol t magic.

DTOT is a way to get blues;) i) is, it is unproductive (, vyde (number of free cyan ples)) of hydrogen in the herodess of hydrophysiology afirov D11x, chorus1; .

PRI memer 1. In a mixture of 59 g of chloral and 30 ml of methanol iniTivHniBifOM and 10% of powdered sodium powder 85% of sodium cyanide, and then a solution of 16 g of sodium hydroxide is IBO ml of methanol. (1 mixture of yyyyyi with reverse x () ,. chpp11 () m K) min., Diluted with 1 of 500 ml of water. iii H6fii.-iniO 10 ml of the 36 ° o-and () th form, 1 nm, then take 10 min. for 10 minutes, 1 odd 1 ,,. yi; cycHoii cn.lotop to sour peai; nirn to litmus n after this one (k-relnut into separating roller. Separated oil (slime11 layer) is separated. release1 of calcium chloride and distilled. It is obtained 18, (J g motllo) 1-dichlorohydrate ether with boiling point 140-143, which is 28% of the yield.

Example 2. Into a mixture of 59 g of chloral, 100 ml of methanol and (ml of cyanhydrin of Belzaldepsche vostoponno lo drops of oil exchange inio 36 g of trietplamine. The mixture is boiled for 15 minutes, diluted with 300 ml of water, then 10 ml 36% formalin, rinse for 10 minutes and then hydrated with hydrochloric acid to acidic to congo. Separate oil is separated, twice broken with its 10% sodium sulfate solution to remove bonsaldehyde and distilled with water nars. the oil is separated from the aqueous layer, dried with calcium chloride and again distilled. . To give 39.5 g of the ester that is 69% from that calculated.

Example 3. To use 520 g of chloral, 300 ml of methanol and 40 M.I. of acetone cyanohydrin with intensive peregnetization for 15 minutes. a solution of magnesium metnat, obtained from 50 g of magnesium and 300 ml of methanol, is added. The addition of magnesium methoxide is accompanied by an increase in the temperature of the mixture to 69 °.

At the end of the addition of magnesium methoxide, the reaction mixture was stirred for 15 minutes, cooled to 30 °, 2 liters of water and 100 M.TI of 36% formalin was added, then unmixed 15 mgsh., Then acidified with hydrochloric acid and the separated oil that is distilled with water. The distilled oil is separated from the aqueous layer, dried over calcium chloride and distilled. 39.2 g of the singing fraction to 141 ° are obtained, and 387.2 g of ether boiling at 141 - 148, which constitutes a yield of 68% of the calculated one.

Subject invention

The method for obtaining the dichloroacetic acid efnrov from chloral, hydrocyanic acid derivatives and alkaline agent in an alcoholic medium is neutralized with the addition of formalin at the end of the process, and as the source of hydrocyanic acid for synthesis are cyanhydrin aldehyde or ketone; as an alkaline agent, a tertiary amine or an alcoholate magn.