Structure and Reactivity of One- and Two-Electron Oxidized Manganese(V) Nitrido Complexes Bearing a Bulky Corrole Ligand.

As a strategy to design stable but highly reactive metal nitrido species, we have synthesized a manganese(V) nitrido complex bearing a bulky corrole ligand, [Mn V (N)(TTPPC)] - ( 1 , TTPPC is the trianion of 5,10,15-Tris(2,4,6-triphenylphenyl)corrole). Complex 1 is readily oxidized by 1 equiv of Cp 2 Fe + to give the neutral complex 2 , which can be further oxidized by 1 equiv of [( p -Br-C 6 H 4 ) 3 N •+ ][B(C 6 F 5 ) 4 ] to afford the cationic complex 3 . All three complexes are stable in the solid state and in CH 2 Cl 2 solution, and their molecular structures have been determined by X-ray crystallography. Spectroscopic and theoretical studies indicate that complexes 2 and 3 are best formulated as Mn(V) nitrido π-cation corrole [Mn V (N)(TTPPC +• )] and Mn(V) nitrido π-dication corrole [Mn V (N)(TTPPC 2+ )] + , respectively. Complex 3 is the most reactive N atom transfer reagent among isolated nitrido complexes; it reacts with PPh 3 and styrene with second-order rate constants of 2.12 × 10 5 and 1.95 × 10 -2 M -1 s -1 , respectively, which are >10 7 faster than that of 2 .