One-pot synthesis of N,N-dimethylaniline from nitrobenzene and methanol

Abstract

A route for the direct synthesis of N,N-dimethylaniline from nitrobenzene and methanol was developed through the sequential coupling of the hydrogen production from methanol, hydrogenation of nitrobenzene to produce aniline, and N-methylation of aniline over a pretreated Raney-Ni® catalyst (at 443 K in methanol). A high yield of N,N-dimethylaniline up to 98% was obtained by the proposed methodology. In this process, aniline was produced from in-situhydrogenation of nitrobenzene with hydrogen generated from methanol, or transfer hydrogenation of nitrobenzene with methanol as donor, while methanol acted as a hydrogen source, alkylating reagent and solvent, simultaneously. Additionally, a plausible mechanism of this one-pot reaction process has been described.