Abstract

Cyclic condensation reactions of various aromatic and heterocyclic aldehydes have been carried out with 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide and o-aminobenzamide by using Amberlite IR-120H resin to afford the corresponding pyramidin-ones and quinazolin-ones in good yield. Further it is of interest to note that cyclisations in catalyzed media are dramatically accelerated to afford pyrazolo[4,3-d] pyrimidin-7(4H)-ones and dihydroquinazolin-4(1H)-ones. This procedure works efficiently in various concentrations of amberlite IR-120H resin and different solvent media under reflux conditions. In the end the catalyst has been recovered and reused up to four cycles without significant loss of activity

Keywords

5-Arylpyrazolo[4,3-d]pyrimidin-7(4H)-ones, 2-aryldihydroquinazoline-4(1H)-one, 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide, o-aminobenzamides and amberlite IR-120H resin