Abstract Thiazolo [5, 4-d] pyrimidines are important class of heterocyclic compounds possessing diverse range of biological activities. Herein, we report an efficient synthesis of thiazolo [5, 4-d] pyrimidines using recyclable KF/alumina catalyst. The reaction of 4, 6- dichloro-5-aminopyrimidine with isothiocyanates in presence of 20 mol% KF/alumina produced thiazolo [5, 4-d] pyrimidines in excellent yields without any chromatographic ...