N2 Reduction into Silylamine at Tridentate Phosphine/Mo Center: Catalysis and Mechanistic Study

Transition-metal-catalyzed formation of silylamine from N-2 (i.e., dinitrogen reduction) is achieved here using a tridentate phosphine/Mo system. Starting from the Mo(O) dinitrogen complex, stepwise reactions with chlorosilanes allowed the synthesis of the Mo(IV) hydrazido complex. Further reaction with two electrons resulted in the N-N bond splitting and formation of bis-silylamide and Mo(IV) nitrido complex. Facile addition of chlorosilane on the nitrido complex was observed to lead to the Mo(IV) imido complex. The four complexes (i.e., Mo(O) dinitrogen, Mo(IV) hydrazido, nitrido, and imido) perform equally well in the catalytic process between stoichiometric amounts of K and chlorosilane under N-2 and are thus likely catalytic intermediates.