One-Pot Three-Component Synthesis of 1-Amidoalkyl-2-naphthols Derivtives by using Sulfamic Acid-Supported Piperidine-4-carboxylic Acid (PPCA) Functionalized Fe3O4 Nanoparticles as Highly Efficient and Rec clable Catalyst

1-Amidoalkyl-2-naphthol derivatives are important class of compounds as they can be easilyconverted to biologically active compounds, 1-aminoalkyl-2-naphthols, by amide hydrolysisreaction [1]. The synthesis of 1-amidoalkyl-2-naphthols can be carried out by multicomponentcondensation of aldehydes, 2-naphthol and amide in the presence of various catalystssuch as SnCl4.5H2O, Nano-sulfated zirconia, dodecylphosphonic acid, and Bi(NO3)3.5H2O [2-4]. However, some of these methods are not environmentally friendly and suffer from one ormore disadvantages, such as prolonged reaction times, low yields, toxicity and recovery andreusability of the catalyst. The demand for environmentally benign procedure with heterogeneousand reusable catalyst, promoted us to develop a safe alternate method for the preparationof amidoalkylnaphthols. In this study, we describe the catalytic activity of sulfonic acidsupported piperidine-4-carboxylic acid functionalized Fe3O4 (Fe3O4–SAPCA) as a novel catalystfor one-pot synthesis of 1-amidoalkyl-2-naphthols by one-pot three-component couplingof β-naphthol, aromatic and aliphatic aldehydes and urea or amides under solvent free (Fig.1). (***) This method offers several advantages including short reaction time, excellent yield, simplework-up, ease of separation, and recyclability of the magnetic catalyst, as well as the ability totolerate a wide variety of substitutions in the reagents.