Fluoroethyl fluoroacetate and related compounds

In view of the fact that fluoroethanol is as toxic as methyl fluoroacetate (or as fluoroacetic acid), it seemed worth while preparing a compound in which the active parts of these molecules were combined, in the hope of obtaining a compound of increased potency. Such a compound is 2-fluoroethyl fluoro-acetate, first prepared and described by us in 1943. This ester was readily prepared by the action of fluoroacetyl chloride on fluoroethanol. It is a stable, mobile hquid possessing an extremely faint odour. 

2-Fluoroethyl fluoroacetate was found to possess rather enhanced toxic properties. The l.c. 50 by inhalation for rabbits was 0 05 mg./I. This shows that it is about twice as toxic (weight for weight) as fluoroethanol or methyl fluoroacetate. This seems to indicate that the toxicity of 2-fluoroethyl fluoroacetate cannot be due entirely to that of its hydrolysis products according to the equation 

Ethyl fluoroacetate 2 (9iIoroethyI fluoroacetate 2-FluoroethyI acetate 2 FluoroethyI chloroacetate 2 FluoroethyI fluoroacetate Phenyl fluorothiolacetate 2-ChIoroethyI fluorothiolacetate 

Toxicity compared to that of methyl fluoroacetate Similar Bather higher 

Lower by mjection considerably lower by inhalation Very slightly less 

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