Air-stable Nickel Research Articles

Pyridine functionalized alkyls of transition metals. Synthesis of bis[C,N-2-pyridylbis(trimethylsilyl)methyl]nickel

Alternate lithiation and reaction with ClSiMe 3 of 2,6-dimethylpyridine gave the lithium derivatives of pyridine substituted at the 2- and 6-positions by mono- or bis(trimethylsilyl)methyl groups. The relative ease of formation of these compounds is discussed and compared to their reactivity with transition metal halides. The reaction of NiCl 2 with the lithium derivative of bis(trimethylsilyl)methylpyridine gives the remarkably air-stable nickel(II) alkyl bis[C,N-2-pyridylbis(trimethylsilyl)methyl]nickel(II).

ChemInform Abstract: SYNTHESIS OF PYRAZOLYL‐BORATE, ‐ALUMINATE, ‐GALLATE, AND ‐INDATE LIGANDS, AND THEIR CHELATING PROPERTIES TOWARDS COBALT(II), NICKEL(II), COPPER(II), AND ZINC(II)

AbstractDie einfach‐negativen Bis‐[pyrazolyl]‐gallat‐Ionen werden durch Umsetzung entsprechender Na‐pyrazolide mit Trimethyl‐Ga in THF synthetisiert und als Na‐ oder Tetraalkylammonium‐Salze (Ia) isoliert.

Synthesis of pyrazolyl-borate, -aluminate, -gallate, and -indate ligands, and their chelating properties towards cobalt(II), nickel(II), copper(II), and zinc(II)

The uninegative dimethylbis(pyrazol-1-yl)- and bis(3,5-dimethylpyrazol-1-yl)dimethyl-gallate ions have been isolated as their sodium and tetra-alkylammonium salts. The anions act as bidentate chelating agents towards transition-metal ions. The orange air-stable nickel complex [Ni{Me2Ga(pz)2}2](pz = pyrazolyl) has a square-planar arrangement of four nitrogens about the nickel atom, while the purple oxygen-sensitive cobalt complex [Co{Me2Ga(pz)2}2] exhibits the transition metal in a tetrahedral environment. Steric requirements of the two ligands are emphasised in the two copper complexes [Cu{Me2Ga(pz)2}2] and [Cu{Me2Ga(dmpz)2}2](dmpz = 3,5-dimethylpyrazolyl) which, respectively, display the copper atoms in square-planar and pseudo-tetrahedral environments. The [Me2B(pz)2]– ligand has been synthesized and utilized to prepare nickel(II), copper(II), and zinc(II) complexes for comparative purposes. Representative pyrazolyl-aluminate and -indate ligands have also been synthesized, but attempts to complex these with transition-metal ions have so far proved unsuccessful.