A Mild and Effective ZnBF4 Catalyzed Protocol for Amidoalkyl Naphthol Synthesis

An effective and efficient protocol has been developed for the synthesis of 1-amidoalkyl-2-naphthols which are biologically active organic compounds having prime place in the field of pharmaceuticals products. In this protocol, the synthesis was carried out using differentially substituted aromatic aldehydes, β-naphthol and amide derivatives via multicomponent pathway in presence of aqueous solution of Zinc tetrafluoroborate (ZnBF4) in Ethanol as catalyst. The catalyst was found to be heterogeneous and easily separable from reaction medium though it was not found to be reusable in the present reaction system. The use of aqueous solvent offers green nature to the protocol. The overall procedure was found to be simple; reaction rate was high irrespective of nature of aromatic aldehydes and yields were satisfactory.