Ethylene chlorohydrins


Ethylene chlorohydrins

Ethylene chlorohydrins or β-chloroethyl alcohol or 2-chloroethanol is a colorless liquid, b.p. 128oC. It is very useful in organic syntheses since it contains two different reactive groups; e.g., by heating with aqueous sodium cyanide it may be converted into ethylene cyanohydrins, which, on hydrolysis, gives β-hydroxypropionic acid.

HOCH2CH2Cl  +  NaCN      HOCH2CH2CN   +   NaCl   (79-80%)

HOCH2CH2CH   (HCl)     HOCH2CH2CO2H


When glycol is treated with phosphorus trichloride or phosphorus tribromide, the corresponding ethylene dihalide is obtained:

 Ethylene chlorohydrins

Phosphorus tri-iodide, however, produces ethylene. Ethylene di-iodide is formed as an inter mediate, but readily eliminates iodine:


 Ethylene chlorohydrins

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