Synthesis of Unsymmetrical Ureas andS-Thiocarbamates under Catalyst-free Conditions in a [BMIM]BF₄Ionic Liquid

Abstract

Unsymmetrical ureas and S‐thiocarbamates were prepared in good to excellent yields by direct condensation of phenylurea with amines and thiols in 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM]BF4) without the addition of any additives. The [BMIM]BF4 ionic liquid is a mild medium and can be recycled and reused several times.

A Facile One-Pot Synthesis of Novel 1,2,4-Triazolo[4,3-a]Pyridine Derivatives Containing the Trifluoromethyl Moiety Using Microwave Irradiation

“…In synthetic chemistry, green methods are attracting interest because of their environmental benefits. 1 Such methods include catalyst free, 2 supercritical fluids, 3 water-phase reactions, 4 ionic liquids, 5 solvent-free reactions, 6 metal-free 7 and ultrasound 8 or microwaves irradiation. 9 Nitrogen-containing heterocycles have also proved attractive andthey have been widely used in the medicinal, agricultural and industrial fields.…”