Alcohol Amination with Ammonia Catalyzed by an Acridine-Based Ruthenium Pincer Complex: A Mechanistic Study

The mechanistic course
of the amination of alcohols with ammonia
catalyzed by a structurally modified congener of Milstein’s
well-defined acridine-based PNP-pincer Ru complex has been investigated
both experimentally and by DFT calculations. Several key Ru intermediates
have been isolated and characterized. The detailed analysis of a series
of possible catalytic pathways (e.g., with and without metal–ligand
cooperation, inner- and outer-sphere mechanisms) leads us to conclude
that the most favorable pathway for this catalyst does not require
metal–ligand cooperation.