Synthesis of [1,2,4]triazolo[4,3-α,]piperazines via highly reactive chloromethyloxadiazoles

A concise, modular approach for the synthesis of [1,2,4]triazolo[4,3-alpha]piperazines via condensation of highly reactive chloromethyloxadiazoles with ethylenediamines is described. NMR studies of this reaction provide evidence that suggests a novel activation mechanism for electrondeficient chloromethyloxadiazoles.