A solvent and transition metal-free, highly efficient Bronsted acidic ionic liquid promoted one-potthree-component reactions for the synthesis of tetrasubstituted pyrroles

摘要

The present protocol describes a highly efficient, transition metal and solvent-free one-pot annulation of amines, dialkyl acetylenedicarboxylates and beta-nitrostyrene using imidazolium Bronsted acidic ionic liquid for the synthesis of tetrasubstituted pyrroles. A diverse functionalized tetrasubstituted pyrroles derivatives were obtained with excellent yields under transition metal and solvent-free conditions. The Bronsted acidic ionic liquid can be easily recovered and reused for the next reaction without any effects on the yields of the products. This green protocol provides structurally complex, medicinally important tetrasubstituted pyrroles with various substitution patterns in a one-pot operation.