| 摘要 |
1,155,518. Purification of #-chloroethane phosphoric acid dichloride. KNAPSACK A.G. 7 Dec., 1967 [23 Dec., 1966], No. 55763/67. Heading C2C. #-Chloroethane phosphonic acid dichloride, contaminated with #-chloroethane phosphate dichloride, is purified by heating the crude product with a catalytic amount of a hydrogen halide salt of a tertiary aliphatic, aromatic or heterocyclic amine to between 50‹ and 350‹ C., thermally splitting the contaminant with the resulting formation of 1,2-dichloroethane, hydrogen chloride, phosphorus oxychloride and meta-phosphoric acid, the split products which are volatile at the splitting temperature being continuously expelled from the mixture, and ultimately subjecting the remaining mixture, consisting of metaphosphoric acid and #-chloroethane phosphonic acid dichloride to distillation, if desired under reduced pressure, to isolate the #-chloroethane phosphonic acid dichloride. Specified catalysts are the hydrogen halide, preferably the hydrochloride, salts of trimethyl, triethyl and triphenyl amines, pyridine, quinoline and phenothiazine. |
