ULTRASONICALLY PROMOTED SYNTHESIS OF TACRINE ANALOGS IN THE PRESENCE OF TIO2 NANOTUBES

Abstract

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.