Efficient Ruthenium-Catalyzed N-Methylation of Amines Using Methanol

摘要: An in situ-generated complex from [RuCp*Cl2]2 and dpePhos ligand is reported as an efficient catalyst the presence of 5 mol % LiOtBu for N-methylation amines using methanol methylating agent at moderate conditions, following hydrogen borrowing strategy. This simple system provides selective N-monomethylation substituted primary anilines sulfonamides well N,N-dimethylation aliphatic excellent yields 40–100 °C with good tolerance to reducible functional groups. The catalytic intermediate Cp*Ru(dpePhos)H was isolated shown be active methylation absence base.