The electrochemical reduction of dinitrogen to ammoniaholds great promise as a sustainable route to fertilizers and fuels, butlittle is known about the detailed mechanism of electrochemical ammoniasynthesis facilitated by molecular or materials catalysts. We aredeveloping robust pincer complexes to model theelectrochemical N2 reduction to NH3 in a well-definedreaction sequence that centers on the direct, dissociative cleavage ofN2 into nitride ligands. Molecular-level mechanistic insight and anunderstanding of the factors that control reductive N2 splittingto form metal nitride complexes will be presented. Subsequentproton-coupled electron transfer (PCET) reduction of nitride complexes canproduce ammonia. Design principles relevant to the development ofmolecular electrocatalysts for challenging multi-proton/multi-electrontransformations, such as N2 reduction, will be discussed.