v-Triazolines. Part 12. Synthesis of 5-amino-1-aryl-4-methylene-4,5-dihydro-v-triazoles

Abstract

A series of 5-amino-4-aminomethyi-1-aryl-4,5-dihydro-v-triazoles was synthesized. On reaction with methyl iodide or methyl trifluoromethanesulphonate the corresponding 4-(quaternary)ammoniomethyl salts were obtained. These derivatives, on treatment with several bases under various conditions, underwent a β-elimination yielding 5-amino-1-aryl-4-methylene-4,5-dihydro-v-triazoles. In the presence of methoxide the methylene derivatives afforded 1-aryl-4-methoxymethyl-v-triazoles via nucleophilic addition and elimination of amine. On reaction with non-nucleophilic bases the methylene compounds were isomerized to 5-amino-1-aryl-4-methyl-v-triazoles.