ULTRASONICALLY PROMOTED SYNTHESIS OF TACRINE ANALOGS IN THE PRESENCE OF TIO2 NANOTUBES
Keywords:tacrine analogs, TiO2 nanotubes, one-pot condensation, synergistic effect, ultrasonic process
The synergistic effect of TiO2 nanotubes and ultrasonication in promoting efficient synthesis of tacrine derivatives from 2-amino-3cyanopyridine and cyclic ketones at room temperature was investigated. In this synthesis, the synergistic effect between Lewis acid and base sites on TiO2 nanotubes and intercalation of reactants as guest molecules into TiO2 nanotubes as host nanoreactors promoted by ultrasonication was crucial to the cyclization step. The current method showed advantages such as easy recovery and recycling of nano-catalyst, simple experimental procedure, environmentally benign conditions, and good yields of the products.