2-fluoroethyl thiocyanate

An attempt to prepare 1 -bromo-2-fluoroethane by the partial fluorination of ethylene dibromide by means of antimony trifluoride was not very successful. The compound was best prepared by the action of phosphorus tribromide on F.E.A. The compound was relatively non-toxic and the bromine atom rather unreactive, but considerably more reactive than the chlorine atom in chlorofluoroethane. For example, bromofluoroethane was readily converted by means of potassium thiocyanate into 2-fluoroethyl thiocyanate. As a lethal inhalant the toxicity of the thiocyanate was inferior to that of M.F.A. Toxicity by injection, however, appeared to be higher. 

By employing the method similar to that of Johnson and Douglass1 for converting SON into S02C1, fluoroethyl thiocyanate was readily converted by the action of chlorine water into 2-fluoroethylsulphonyl chloride, a stable liquid. When small animals were exposed to the vapour at a concentration of 0-5 mg./l. for 10 min., irritation and lacrimation were caused, but there were no deaths and all the animals recovered. 

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