Efficient solvent free synthesis of tetrahydrobenzo[<i>a</i>]xanthene-11-one derivatives using nano-AlPO₄/Ti (IV) as a green, heterogeneous and reusable catalyst

A new green protocol has been developed for synthesis of tetrahydrobenzo[<i>a</i>]xanthen-11-ones <i>via</i> a three component, one-pot condensation reaction of dimedone, <i>β</i>-naphthol and aromatic aldehydes using nano-AlPO_4/Ti (IV) (NAP-Ti(IV)) as a reusable and novel catalyst at 90 °C under solvent-free condition. Short reaction times, high yields, scale up and easy work-up are advantages of this protocol. The prepared nano-AlPO_4/Ti(IV) was fully characterized by EDX, XRD, SEM, IR analysis. The obtained tetrahydrobenzo[<i>a</i>]xanthen-11-ones were characterized by various methods such as FT-IR, ¹HNMR.