Phosgene → (2-Chloroethyl)phosphonic dichloride

Participants

Reaction Steps

298 g of the vinylphosphonic acid derivatives thus prepared are metered into 300 g of vinylphosphonic acid dichloride at 145° C. during the course of 4 hours, whilst stirring, during which time phosgene gas is continuously introduced into the reaction mixture. The reaction mixture is then further phosgenated for 10 hours at this temperature. 1,2-Dichloroethane which is formed distils off during the phosgenation. After the phosgenation has ended, the excess phosgene is stripped off at room temperature in the vacuum from a water jet. The mixture is then distilled at 2 mm Hg with the aid of a column. 430 g of vinylphosphonic acid dichloride and 140 g of 2-chloroethanephosphonic acid dichloride are obtained. The distillation residue is 39 g. 130 g of vinylphosphonic acid dichloride and 140 g of 2-chloroethanephosphonic acid dichloride were thus prepared from 298 g of vinylphosphonic acid derivatives. The 2-chloroethanephosphonic acid dichloride can again be employed as the reaction medium in a second mixture, instead of the vinylphosphonic acid dichloride.

Provenance & Evidence