2-fluoroethyl chlorosulphonate

In class B are placed all simple esters, CHjF CO i , of fluoro-aoetic acid, where iZ = Me, Et, Pr , Pr , Ph, etc. When substitution takes place in the a-hydrogen atoms, e.g. in methyl a-fluoropropionate or a-fluoroisobutyrate, then the compound is devoid of toxicity. This indicates the importance of the unsubstituted fluoromethyl group. On pp. 125 et seq. it was shown that fluoroacetamide and a variety of substituted amides such as CHjF CO NH CHg CHjCl were, molecule for molecule, equally toxic with fluoroacetic acid and produced the same symptoms. The 2 chloroethyl group therefore contributed nothing appreciable to the toxicity of the molecule. The majority of the esters of fluoroethanol showed the toxicity of the parent alcohol, e.g. 2-fluoroethyl chlorosulphonate, CHgF CHg O SOjCl, di-(2-fluoroethyl) sulphate and 2-fluoroethylglycine hydrochloride. 

On exposing animals for 10 min. to 0-327 g./cu.m. of the chlorosulphonate, irritation was observed and rats showed the same type of convulsions as with M.F.A. However, only 2/13 of a batch of rabbits, guinea-pigs and rats died within 24 hr. The difluorodiethyl sulphate was non-irritant and less toxic. It proved to be a good fluoroethylating agent. 

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