Amidoximes, obtained from the reaction of nitriles with hydroxylamine, underwent Tiemann
rearrangement in the presence of benzenesulfonyl chlorides (TsCl or o-NsCl) to form the N-substituted cyanamides. Subsequently, acidic hydrolysis of the
cyanamides afforded the corresponding N-monosubstituted ureas. The synthesis of N-monosubstituted
ureas from nitriles was accomplished by three steps in one pot, which provides a direct
access to versatile N-monosubstituted urea derivatives from a wide variety of nitriles.
Key words
urea - cyanamide - amidoxime - hydrolysis - Tiemann rearrangement