Kaolin-SO3H as a new solid acid is prepared via reaction of kaolin and chlorosulfonic acid. This natural based catalyst is very inexpensive and easy available. Imidazoles are an important class of heterocycles being the core fragment of different natural products and biological systems such as anti-allergic, anti-inflammatory, analgesic, antifungal, antimycotic, antibiotic, antiulcerative, antibacterial, antitumor and […]
Tetrazoles have many interesting futures and applications in drug and energy industries. 5-Substituted 1H-tetrazoles were synthesized via [2+3] cycloaddition reaction of aryl or alkyl nitriles with sodium azide in the presence of [email protected] as catalyst in DMF under reflux conditions. The catalyst was removed from reaction mixture by an external magnet and was reusable for […]