A cycle for organic nitrile synthesis via dinitrogen cleavage

In the presence of NaH, the reaction between N2 and Mo(Nt-Bu]Ar)3 (Ar = 3,5-C6H3Me2) proceeds at room temperature to afford NMo(Nt-Bu]Ar)3 (95%). Lewis acidic silyl triflates (Me3SiOTf + pyridine or (i-Pr)3SiOTf) mediate a reaction between acid chlorides and NMo(Nt-Bu]Ar)3 to yield acyl imidos RC(O)NMo(Nt-Bu]Ar)3]OTf] (R = Me, 92%; Ph, 75%; t-Bu, 64%). The reduction of RC(O)NMo(Nt-Bu]Ar)3]OTf] by magnesium anthracene followed by treatment with Me3SiOTf affords molybdenum ketimides, R(Me3SiO)CNMo(Nt-Bu]Ar)3 (R = Me, 82%; Ph, 77%; t-Bu, 46%). Exposing R(Me3SiO)CNMo(Nt-Bu]Ar)3 to SnCl2 or ZnCl2 produces ClMo(Nt-Bu]Ar)3 (71-93% for SnCl2) and RCN (97-99%). Magnesium metal reduces ClMo(Nt-Bu]Ar)3 to Mo(Nt-Bu]Ar)3 (74%), completing a synthetic cycle. New strategies for the functionalization of sterically hindered nitrides and nitrile extrusion from d2 ketimides are presented in the context of a new route for derivatizing N2.