Superparamagnetic Fe₃O₄ Nanoparticles in a Deep Eutectic Solvent: An Efficient and Recyclable Catalytic System for the Synthesis of Primary Carbamates and Monosubstituted Ureas

Abstract

Superparamagnetic Fe 3 O 4 nanoparticles were used to synthesize various primary carbamates as well as monosubstituted and N , N ‐disubstituted ureas. This efficient phosgene‐free process used urea as an eco‐friendly carbonyl source in the presence of a biocompatible deep eutectic solvent (DES) to provide an inexpensive and attractive route that afforded the products in moderate to excellent yields. The employed DES serves both a catalytic role and as the green reaction medium. The magnetic nanocatalyst and DES can been reused several times without a significant loss of activity.