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)NiBrLi(thf)(OEt) (L = PhC(NBu), Ar = 2,6-iPrCH, 1) with NaHBEt led to intramolecular C-H activation with the formation of the μ-1,2-dinitrogen dinickel pincer complex [LSi(NAr)(NAr)Ni](μ-1,2-N) (Ar = 2-C(CH)-6-iPrCH, 2). Single-crystal X-ray diffraction analysis of 2 disclosed a square planar Ni(II) atom bridged by N. 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. These results provide new approaches for the coordination of N with nickel(II) species.