Reaction of Phenyl Iso(thio)cyanate with N‑Heterocyclic Carbene-Supported Nickel Complexes: Formation of Nickelacycles

The nickel­(I) complex [(η5-Cp)­Ni­(IPr)] (Cp = cyclopentadienyl, IPr = 1,3-bis­(2,6-diisopropylphenyl)­imidazolin- 2-ylidene) reacts with phenyl isothiocyanate to afford the new heteronickelacycle [(IPr)NiSC­(NPh)­N­(Ph)CS] (1), which contains the novel bidentate and dianionic ligand {SC­(NPh)­N­(Ph)­CS}2–. Complex 1 is also obtained from the nickel(0) compound [(IPr)­Ni­(styrene)2] with two equivalents of PhNCS. The γ-lactam-nickelacycle [(IPr)NiN­(Ph)­C­(O)­CH2CH­(Ph) (3) is formed from [(IPr)­Ni­(styrene)2] and one equivalent of phenyl isocyanate. Complex 3 is a rare example of a nickel­(II) complex with a T-shaped structure. Compounds 1 and 3 were characterized by X-ray crystallography, 1H and 13C NMR spectroscopy, UV–vis spectroscopy, and elemental analysis.