Efficient Methylation Of Anilines With Methanol Catalysed By Cyclometalated Ruthenium Complexes

Cyclometalated ruthenium complexes 4-10 allow the effective methylation of anilines with methanol to selectively give N-methylanilines. This hydrogen autotransfer procedure proceeds under mild conditions (60 degrees C) in a practical manner (NaOH as base). Mechanistic investigations suggest an active homogenous ruthenium complex and beta-hydride elimination of methanol as the rate determining step.