Recent Progress in Dinitrogen Activation by Gas-Phase Metal Species.

Understanding the mechanisms to activate and functionalize dinitrogen (N 2 ) is of great importance for the rational design of nitrogen-fixation catalysts. Reactions of gas-phase species with N 2 are being actively studied to understand the bond activation and formation processes at a strictly molecular level. This Perspective provides an overview of the recent progress in combined experimental and theoretical studies on the activation and functionalization of N 2 by gas-phase metal species. New mechanistic insights into N 2 molecular adsorption, N≡N cleavage, and N-X (X = C, B, and H) formation have been introduced, in which the new reaction channels of ejecting neutral metal fragments and the coupling reactions of N 2 with other molecules are highlighted. Finally, the current challenges and outlooks of N 2 activation in the gas phase are discussed as well.