Ionic liquid 1,3-disulfonic acid imidazolium hydrogen sulfate: a novel and highly efficient catalyst for the preparation of 1-carbamatoalkyl-2-naphthols and 1-amidoalkyl-2-naphthols

Abstract

In this work, a novel ionic liquid, 1,3-disulfonic acid imidazolium hydrogen sulfate {[Dsim]HSO₄}, with a Brønsted acidic property, is synthesized, and used as a highly efficient, green, recyclable and homogeneous catalyst for the preparation of 1-carbamatoalkyl-2-naphthols and 1-amidoalkyl-2-naphthols under solvent-free and relatively mild conditions. The one-pot multi-component condensation of β-naphthol with arylaldehydes and alkyl carbamates or amides affords the title compounds in high yields and in short reaction times.