Another application of newly prepared Brønsted-acidic ionic liquids as highly efficient reusable catalysts for neat synthesis of amidoalkyl naphthols

Abstract In this work, two newly prepared Brønsted-acidic ionic liquids, [MPyrrSO3H]Cl (IL1) and [MMorSO3H]Cl (IL2), were efficiently used as catalysts for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide under neat conditions. High activity of the catalysts, excellent yields, short reaction times, simple procedure with an easy work-up, and the absence of any volatile and hazardous organic solvents are some advantages of the present methodology. Moreover, the catalysts are simply prepared and can be recovered conveniently and reused such that considerable catalytic activity can still be achieved after the fifth run.