DE559521C - Process for the complete separation of 1-phenyl-1íñ2-dichloroethane from a mixture with 1-phenyl-1-oxy-2-chloroethane - Google Patents

Description

Process for the complete separation of 1-phenyl-1 - 2-dichloroethane from a mixture with 1-phenyl-1-oxy-2-chloroethane in the addition of hypochlorous Acid on styrene (phenylethylene) is always a mixture of i-phenyl-i-oxy-2-chloroethane and i-phenyl-i # 2-dichloroethane. You can use fractional distillation To a large extent separate the two connections, but never completely win them.

As has been found, one can be indifferent in such a mixture whether it contains much or little of the dichloro compound, its complete separation bring about, if it is in .an immiscible with water organic solvent, z. B. benzene, dissolves and now with or without temperature increase and in the presence or Treated in the absence of water with alkali or alkaline earth oxides or hydroxides. The i-phenyl-i-oxy-2-chloroethane present goes into the low-boiling phenylethylene oxide over, which can be easily distilled off. Pure i-phenyl-i # 2-dichloroethane remains return.

It is surprising that i-Phenyli # 2-dichloroethane among the conditions described is not attacked, as it is when treated with aqueous or alcoholic alkali hydroxide without water-insoluble organic solvent converts into phenylchlorethylene. The pure i-phenyl-i # 2-dichloroethane can serve to represent i-phenyli-oxy-2-chloroethane.

Example i A mixture of 156.5 parts of i-phenyl-oxy-2-chloroethane and 175 parts of i-phenyl # 2-dichloroethane are mixed with 600 parts of benzene. In addition a solution of 170 parts of potassium hydroxide in 100 parts of water flows with stirring. The temperature rises to about ¢ 2 °, and potassium chloride separates out. As soon as the reaction has stopped, water is added and the benzene solution is separated and washes them alkali-free. After the benzene has been distilled off, the residue becomes repeatedly fractionated. One obtains 10 8 parts -. 90 o / a of the theory of phenylethylene oxide from Kps, n ", 7o ° and gains 15o to 16o parts of i-phenyl-i # 2-dichloroethane in pure form Shape back.

Potassium hydroxide can also be used in solid form or as a more dilute solution use or replace it with sodium hydroxide, barium hydroxide, etc.

Instead of benzene you can. use other hydrocarbons or their derivatives, such as tetrachloroethane, trichloroethane, chlorobenzene, ether, benzyl alcohol and the like. At- instead of 42 ° you can use a lower or work at a higher temperature. 'Example 2 One made from 98% i-phenyl-i # 2-dichloroethane and 2% i-phenyl-i-oxy-2-chloroethane of the mixture is, as in example i, with Potassium hydroxide solution treated. It kicks only a slight increase in temperature, and little potassium chloride precipitates. To the work-up is obtained from the rectification cation has a low forerunner of phenyl ethylene oxide, then distilled very pure i-Phenyl-i # 2-dichloroethane of b.p .; mm 93` in almost quantitative amounts. Example 3 A 98% i-phenyl-i-oxy-2-chloroethane and 2% i - phenyl-i # 2-dichloroethane standing mixture is according to example i acts. When the oil is distilled, the main amount, consisting of phenylethylene oxide, is transferred up to about 70 ° under 5 mm pressure. The residue remaining at 80 ° under 5 mm pressure shows a chlorine content of about 38% (pure phenyl dichloroethane contains 40-57%, pure phenyloxychloroethane 25 # 2% chlorine). In its rectification, pure i-phenyl-i # 2-dichloroethane with a bp 5 mm 93 ° is obtained.

Claims (1)

PATENT CLAIM: Process for the complete separation of i-phenyl-i. 2-dichloroethane from a mixture with i-phenyl-i-oxy-2-chloroethane, characterized in that that the mixture, dissolved in a water-immiscible organic solvent, treated with alkali or alkaline earth oxides or hydroxides.