Strategy Used to Control the Mechanism of Homogeneous Alkyne/Olefin Hydrogenation: AIMD Simulations and DFT Calculations

Understanding
the mechanism of the catalytic reaction is an effective
way to design new high-performance catalysts. The mechanisms of alkyne/olefin
hydrogenations catalyzed by a nonclassical Co–N2 catalyst are explored by ab initio molecular dynamics simulations
and density functional theory calculations. From the calculated results,
the hydrogenation mechanisms, i.e., molecular or atomic mechanisms,
can be effectively controlled via employing the different interaction
between the catalyst and substrates. The origination of excellent
selectivity toward E-olefins for the Co–N2 catalyst is also taken into account with the help of investigating
the olefin hydrogenation process. The mechanism indicates that the
negligible energy barrier of rotation is the main reason for highly
selective semihydrogenation of a Co–N2 catalyst,
which leads to the trans-olefin formation. These
investigations may provide some useful information and guidelines
on the current understanding of the hydrogenation reaction and designing
the high-performance catalysts.