Application of tropine as a suitable base for the preparation of an activecatalyst in acceleration of synthesis of ۱,۲,۴-triazolo[۴,۳-a]pyrimidines

In recent years, dicationic ionic liquids (DILs) have attracted increasing interest, findingunique applications as electrolytes, stationary phases in gas chromatography, lubricants,catalysts, fuel cells, solar cells, solvents in high temperature organic reactions [۱].DIL’s cationicheads, the linker and the outer chains caused structural variability, high tunability, low volatility,high thermal stability and lower ecotoxicity to compare with parental monocationic ionic liquids.Tropine or ۳-tropanol is an important member of azabicyclo compounds which contain a tropanering.Pyrimidine and its derivatives are important heterocyclic compounds and the diversity oftheir chemical and biological importance have made them more vital in pharmaceuticalchemistry [۲]. On the other hand, triazole is a five-membered heterocycle with three nitrogenatoms which one of its isomers is ۱,۲,۴-triazole. Among these compounds ۳-amino[۱,۲,۴]triazolederivatives which are composed of two rings, one pentamerous and the other senary, connectedby a nitrogen bridge, have the ability to induce the growth of the cancer cells in the thyroid glandof rats [۳].In this work, a green and efficient procedure is reported for the synthesis of ۱,۲,۴-triazolo[۴,۳-a]pyrimidine derivatives using a suitable dicationic molten salt based on tropine([(Tropine)۲C۳H۵OH].۲Cl). The simple catalyst preparation, straightforward separation andrecovery of the catalyst from the reaction mixture, simple work-up method requiring no specialseparation procedure, solvent-free conditions, short reaction timesand high yields of the productsare the significant points of interest of this study.