Synthesis and reactivity of a μ-1,2-dinitrogen dinickel(II) complex with a C-H activated silaamidinate pincer ligand.

Reaction of the silaamidinate nickel bromide LSi(NAr) 2 NiBr 2 Li(thf)(OEt 2 ) (L = PhC(N t Bu) 2 , Ar = 2,6-iPr 2 C 6 H 3 , 1) with NaHBEt 3 led to intramolecular C-H activation with the formation of the μ-1,2-dinitrogen dinickel pincer complex [LSi(NAr)(NAr)Ni] 2 (μ-1,2-N 2 ) (Ar = 2-C(CH 3 ) 2 -6-iPrC 6 H 3 , 2). Single-crystal X-ray diffraction analysis of 2 disclosed a square planar Ni(II) atom bridged by N 2 . Reaction of 2 with carbon monoxide and 2,6-dimethylphenyl isocyanide yielded square planar carbonyl and isocyanide complexes 3 and 4 with release of N 2 . These results provide new approaches for the coordination of N 2 with nickel(II) species.