Environmentally friendly preparation of amidoalkyl naphthols

A new, facile, and cost-effective process involving the solvent-free synthesis of amidoalkyl naphthols using a three-component, one-pot condensation reaction of -naphthol, aromatic aldehyde, and amides in the presence of Al(H2PO4)(3) as heterogeneous catalyst under thermal conditions and microwave irradiation has been described. This new approach has the advantage of consistently excellent yields and short reaction times. The catalyst has shown a very stable catalytic activity in the reaction conditions and also can be recovered and recycled.