Isolation and methylation of aroylnickel intermediates derived by carbonylation of trans-aryl(pentachlorophenyl)bis(phenyldimethylphosphine)nickel(II) compounds

Article abstract of DOI:10.1021/ic50187a004

From the reaction of trans-C₆Cl₅Ni(PPhMe₂)₂C ₆H₄X-p (1) with carbon monoxide, three aroylnickel(II) complexes, trans-C₆Cl₅Ni(PPhMe₂)₂C(O)C ₆H₄X-p (2) (X = a, N(CH₃)₂; b, OCH₃; c, CH₃), were isolated. These complexes, 2, react further with carbon monoxide to give C₆Cl₅C(O)C₆H₄X-p (3) but thermally decompose to give C₆Cl₅C₆H₄X-p (5). Methylation by methyl fluorosulfonate occurred at the aroyl oxygen atom of 2 to give cationic aryl(methoxy)carbenenickel(II) complexes, trans-[C₆Cl₅Ni(PPhMe₂)₂ {C(OCH₃)C₆H₄X-p}]⁺ (4). The IR, ¹H NMR, and electronic spectra of 2 were explained with the contribution of resonance forms having an anionic charge on the aroyl oxygen atom. The carbene complexes, 4, are stable thermally, and their ¹H NMR spectra showed a perpendicular relationship between the plane of the carbene ligand and the nickel coordination plane.