Group 6 Transition-Metal/Boron Frustrated Lewis Pair Templates Activate N₂ and Allow its Facile Borylation and Silylation

The reaction of trans-[M(N₂ )₂ (dppe)₂ ] (M=Mo, 1_Mo , M=W, 1_W ) with B(C₆ F₅ )₃ (2) provides the adducts [(dppe)₂ M=N=N-B(C₆ F₅ )₃ ] (3) which can be regarded as M/B transition-metal frustrated Lewis pair (TMFLP) templates activating dinitrogen. Easy borylation and silylation of the activated dinitrogen ligands in complexes 3 with a hydroborane and hydrosilane occur by splitting of the B-H and Si-H bonds between the N₂ moiety and the perfluoroaryl borane. This reactivity of 3 is reminiscent of conventional frustrated Lewis pair chemistry and constitutes an unprecedented approach for the functionalization of dinitrogen.