A Missing Nuclearity in the Co(III)/Ln(III)/2-Pyridyladoxime Chemistry: Tetranuclear Compounds Using the “Assisted Self-Assembly” Approach (Ln = Rare Earth Metals)

Abstract

By employing the HSAB principle and the “assisted self-assembly” approach and using 2-pyridylaldoximate (pao−) as the primary ligand and pivalate (piv−) as the ancillary co-ligand, tetranuclear [CoIII2LnIII2(NO3)4(pao)4(piv)4] complex polynuclear compounds were isolated (Ln = Dy, Gd, Tb, Pr, Y). The structure of the Dy(III) complex was determined via single-crystal X-ray crystallography, revealing a metal topology of two {CoIIIDyIII2} triangles that shared a common DyIII…DyIII edge. Microanalytical, PXRD (for the two first members)d and spectroscopic (IR, EDX) data for all complexes provided strong evidence that the complexes were isostructural. The nuclearity and metal topology of the crystallographically characterized [CoIII2LnIII2(NO3)4(pao)4(piv)4] are new in the previously investigated CoIII/LnIII/pao− chemistry emphasizing utility of the “assisted self-assembly” approach.