Preparation of oxalyl chloride
AssigneeRhone-Poulenc Industries
InventorsAndre Acloque, Jean-Claude Lanet, Yves Correia
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Abstract
Oxalyl chloride is prepared by (i) first esterifying ethylene glycol with trichloroacetyl chloride, (ii) next photochemically chlorinating the ester which results from the step (i), i.e., ethylene glycol bis-trichloroacetate, and (iii) then decomposing the tetrachloroethylene glycol bis-trichloroacetate thus formed into the desired oxalyl chloride and trichloroacetyl chloride, said steps (i) and (iii) being conducted in the absence of any reaction solvent, other than the trichloroacetyl chloride, and the chlorination step (ii) being conducted at a temperature of from about 50.degree. to 200.degree. C.
Claims14
A process for the preparation of oxalyl chloride comprising:
- (i) esterifying ethylene glycol with trichloroacetyl chloride, in the absence of any reaction solvent other than trichloroacetyl chloride, to afford ethylene glycol bis-trichloroacetate, the reaction mixture for the esterification consisting essentially of ethylene glycol, trichloroacetyl chloride and the reaction products thereof, and the hydrochloric acid produced during the esterification being removed from the reaction mixture by distillation;
- (ii) photochemically chlorinating the resulting ethylene glycol bis-trichloroacetate, at a temperature of from about 50.degree. to 200.degree. C., to afford tetrachloroethylene glycol bis-trichloroacetate;
- (iii) decomposing the resulting tetrachloroethylene glycol bis-trichloroacetate, at a temperature of from about 50.degree. to 160.degree. C., in the presence of trichloroacetyl chloride as the sole reaction solvent, and in the presence of a decomposition catalyst, to afford oxalyl chloride and trichloroacetyl chloride;
- and
- (iv) separating the resulting oxalyl chloride.
Dependencies are inferred from the claim text.