Dipotassiumtetrachloride-bridged dysprosium metallocenes: a single-molecule magnet.

The present work describes the dynamic magnetic properties of the complex [(Cp)DyIII2ClK]·3.5(CH) (1), synthesized by employing a tri-aryl-substituted cyclopentadienyl ligand (Cp), [4,4'-(4-phenylcyclopenta-1,3-diene-1,2-diyl)bis(methylbenzene) = CpH]. Each Dy(III)-metallocene weakly couples KCl, displaying slow relaxation of magnetization below 14.

Synthesis, oligomerization and catalytic studies of a redox-active Ni-cubane: a detailed mechanistic investigation.

A robust tetrameric nickel complex [Ni((O )L-Me)(s)] (3) (s = solvent) with cubane-like NiO core topology was isolated as a light greenish-orange crystalline solid in excellent yield. The mechanism of formation of 3 involving the two chloride-containing precursors [Ni((O )L-Me)(s)]·2MeOH (1) and [Ni((O)L-Me)((O )(OH)L-Me)Cl] (2) was studied by ESI mass spectrometry and confirmed by the solid state isolation and single-crystal X-ray diffraction. The challenging ligand fields containing mono/di-anionic ON donating atoms and/or chloride ions stabilized the pentacoordinate Ni(ii) ions in 1-2 upon controlling the experimental conditions.