One-Pot, Solvent-Free Access to Unsymmetrical Ureas by Palladium-Catalysed Reductive Alkylation Using Molecular Hydrogen

International audienceUnsymmetrical N,N′-disubstituted ureas were prepared in 60–93 % isolated yield by palladium-catalysed reductive alkylation of monosubstituted ureas using aldehydes as alkylating agents and molecular hydrogen as a clean reductant. A one-pot, solvent-free sequence was also developed from the corresponding amines