Nickel(II) Schiff base complexes: Synthesis, characterization and catalytic activity in Kumada-Corriu cross-coupling reactions

作者：Kuchtanin Vladimir^*; Klescikova Lucia; Soral Michal; Fischer Robert; Ruzickova Zdenka; Rakovsky Erik; Moncol Jan; Segl'a Peter

来源：Polyhedron, 2016, 117: 90-96.

DOI：10.1016/j.poly.2016.05.037

• Nickel(11) complexes
• Schiff base
• Kumada-Corriu reaction
• Cross-coupling
• Biaryl

The syntheses of ten new Ni(II) complexes 5a-5j with H2L tridentate (ONO) Schiff-base ligand (2-((2-oxybenzylidene)amino)phenolate) have been described and fully characterized by means of elemental analysis, FT-IR, electronic, H-1 NMR and C-13 NMR spectroscopy and single-crystal X-ray diffraction. In all [Ni(L)B] complexes (where B are imidazole, 4-benzylpyridine, 2-methyl-5-ethylpyridine, 3-hydroxymethylpyridine, 2-methylbenzimidazole, 2,6-dimethylpyridine, 4-methylpyridine, 2-isopropylbenzimidazole, 4-methylpiperidine or triphenylphosphine) the Schiff base completely deprotonates and coordinates to the metal ion as a dianionic tridentate ligand via the donor oxygens and nitrogen atoms. The coordination number of Ni(II) atoms is four with distorted square-planar stereochemistry. This is in a good agreement with the ligand field band position in their electronic spectra, as well as with the X-ray structure analysis for all complexes under study. Six selected complexes are used as catalysts for Kumada-Corriu cross-coupling reactions and exhibit a moderate to good catalytic activity in the synthesis of biaryl derivatives.

• 出版日期2016-10-15