A Simple Conversion of Amines Into Monosubstituted Ureas in Organic and Aqueous Solvents
Qi Liu, Nathan W. Luedtke and Yitzhak Tor
A versatile and highly efficient synthesis of monosubstituted ureas is described. The reaction of an amine with 4-nitrophenyl-N-benzylcarbamate, followed by hydrogenolysis, provides the corresponding urea in high yield and purity. This carbamate can also be employed for the derivatization of water-soluble polyamines (e.g. aminoglycoside antibiotics), while other reagents (e.g. benzylisocyanate) fail to give the desired products in any significant yield.