[CTA]Fe/MCM-41: An efficient and reusable catalyst for green synthesis of xanthene derivatives

Iron was incorporated into MCM-41 via direct synthesis and wet impregnation methods. Removal of the surfactant occluded in Fe/MCM-41 pores has been performed by using two procedures: solvent extraction and calcination. For comparison, a series of template-containing mesoporous Fe/MCM-41 were also synthesized without surfactant removal. The catalysts were examined in three component reaction to afford benzoxanthene derivative. A high yield of 91% was achieved over template-containing Fe/MCM-41 catalyst. This high activity is due to both lewis acid sites and ionic template. This catalyst could be easily recovered by filtration and reused without loss of its catalytic activity because the organic template does not leach during the reaction. It is also very efficient for the synthesis of a hydroxanthene derivative.