1.2.4- Triazolo oxadiazoles synthesis

An alternahve method had been reported in the literature [12] to prepare [1,2,4] triazolo[4,3-a]piperazines (Route B, Scheme 5.9) via the condensahon of a chloromethyl oxadiazole with 1,2-phenylenediamine to afford the benzo fused compounds. The reachon condihons reported for this approach were harsh and the yields were low, presumably due to the poor nucleophilicity of 1,2-phenylenedi-amine. However, we felt that the synthesis of 3 could potentially be accomplished under milder reachon condihons because of the enhanced nucleophilicity of... 

Oxadiazoles have been utilized in the synthesis of 1,2,4-triazoles. Condensation of highly reactive chloromethyloxadiazoles 171 with ethylenediamines 172 afforded amidines 173, which under reflux in methanol, gave [l,2,4]triazolo[4,3-a]piperazines 174 <050L1039>. Reaction of... 

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