A Simple One-Pot Procedure for Preparing Symmetrical Diarylureas from Carbon Dioxide and Aromatic Amines

Abstract

Symmetrical diarylureas can be prepared by purging an aromatic amine with carbon dioxide in the presence of a strong amidine base followed addition of solid commercially available Me₃N.SO₃. Work up is simply by dilution with water. The procedure is far simpler and safer than traditional methods using phosgene or isocyanates.