Fe₃O₄/eggshells composite as green catalyst for Hantzsch condensation in acridine synthesis

Acridine derivatives are a class of nitrogen heterocycles which have broad spectrum of important biological properties and pharmaceutical applications. Low-cost eggshells waste material was used as source of CaCO₃ to modified magnetic Fe₃O₄ particles prepared from co-precipitation to serve as reusable heterogeneous catalyst. The synthesized eggshells based catalyst is characterized by X-ray diffraction (XRD) and TEM studies. The activity of the catalyst has been investigated in Hantzsch condensation reaction with good yields and simple work-up procedure. The synthesis of acridine derivative was achieved through a one-pot, three-component condensation of dimedone, aryl amine and aryl aldehydes utilizing Fe₃O₄/eggshells composite as catalyst under mild conditions. Maximum yield obtained is 91.3% with reflux condition, amount of catalyst 0.0254 g, and 1.5 h reaction time. Catalyst used can be separated magnetically and can be reused up to three times without significant decrease of yield. The synthesized compound was characterized using IR, UV-Vis and LC-MS.