Complexes of nickel(II) with aryloxo and functionalized aryloxo ligands

The hydroxo complex (NBu4)(2)[{Ni(C6F5)(2)(mu-OH)}(2)] reacts with aromatic alcohols at room temperature in methanol to give the binuclear complexes (NBu4)(2) [{Ni(C6F5)(2)(mu-OAr)}(2)] (Ar = Ph, C6H4Me-p, C6H4NO2-p, C6F5). The mu-pyrazolate-mu-aryloxo complexes (NBu4)(2)[{Ni(C6F5)(2)}(2)(mu-OAr)(mu-pz)] (Ar = C6H4NO2-p, C6F5) can be prepared by treating (NBu4)(2) [{Ni(C6F5}(2))(2)(mu-OH)(mu-pz)] with the corresponding ArOH. Mononuclear nickel(II) complexes of a variety of deprotonatable bidentate N,OH ligands have been prepared by reaction of (NBu4)(2)[{Ni(C6F5)(2)(mu-OH)}(2)] with 2-aminoethanol, 2-hydroxymethylpyridine, 2-hydroxipyridine, 2-aminophenol and the Schiff-base ligands 2-HOC6H4N=CHR (R=Ph, C6H6Me-p, C6H4MeO-p and C6H4Cl-p). Analytical (C, H, N), conductance and spectroscopic (IR,H-1 and F-19 NMR) data have been used for structural assignments. A single crystal X-ray diffraction study of (NBu4)(2) [{Ni(C6F5)(2)(mu-OC6F5)}(2)] showed that coordination about nickel was square-planar with slight distortion towards a tetrahedral arrangement. The pentafluorophenyl rings are oriented nearly perpendicular to the coordination plane.