Dinitrogen Activation by Dihydrogen and a PNP-Ligated Titanium Complex

The hydrogenolysis of the PNP-ligated titanium dialkyl complex {(PNP)Ti(CH2SiMe3)(2)} (1, PNP = N(C6H3-2-(PPr2)-Pr-i-4-CH3)(2)) with H-2 (1 atm) in the presence of N-2 (1 atm) afforded a binuclear titanium side-on/end-on dinitrogen complex {[(PNPTi](2)(mu(2),eta(1),eta(2)-N2)(mu(2)-H)(2)} (2) at room temperature, which upon heating at 60 degrees C with H-2 gave a mu(2)-imido/mu(2)-nitrido/hydrido complex {[(PNP)Ti](2)(,mu(2)-NH)(mu(2)-N)H} (3) through the cleavage and partial hydrogenation of the N-2 unit. The mechanistic aspects of the hydrogenation of the N-2 unit in 2 with H-2 have been elucidated by the density functional theory calculations.