Dipyridylamine complexes of cobalt(II)

Abstract

The preparation is described of some complexes of cobalt(II) salts with di-2-pyridylamine (= L). Magnetic and electronic spectral studies show that CoL₃(ClO₄)₂, CoL₃I₂, and CoL₂(NCS)₂ are essentially octahedral, whilst CoLX₂(X = Cl, Br, I) have distorted tetrahedral structures. In all compounds the ligand field is comparatively strong, with Δ∼ 11,000 cm.^–1 for [CoL₃)²⁺ but infrared evidence points to co-ordination through the pyridine nitrogen atoms, rather than through the amino nitrogen.