Ruthenium-Catalyzed Selective Mono N‑Ethylation of Arylamines and Tandem Reduction/N‑Ethylation of Nitroarenes Using Triethylamine and Formic Acid

The mono N-alkylation of arylamines using alkylamines as alkyl group donors has been scarcely investigated. In this work, we report the mono N-alkylation of several arylamines (52–95%) catalyzed by the complex ruthenium-triphos in the presence of Al­(OTf)3. Moreover, the highly reductant ability of the catalyst system allows the tandem reduction/N-alkylation of nitrobenzenes in good yields (up to 80%). In addition, the catalyst can be recycled after three reaction cycles without loss of catalyst activity.