An Aroylhydrazone as Chelating Agent: 4f Metal Complexes of 2,6-Diacetylpyridine bis(2-Furoylhydhazone)

Abstract

Two types of complexes, [Ln₂Cl₄(H₂dapf)(H₂O)₆]Cl₂ and [Ln(Hdapf)(OH)₂]₂ [Ln = La(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III) and Dy(III); H₂dapf = 2,6-diacetylpyridine bis(2-furoylhydrazone)], having coordinated neutral (H₂dapf) or uninegative (Hdapf) hydrazones, respectively, have been isolated from the reaction of the lanthanide chloride and the hydrazone in neutral and slightly alkaline solutions, respectively. The complexes were characterized by elemental analyses, molar conductance, TGA and DTA, magnetic susceptibility, electronic, infrared and NMR (¹H and ¹³C) spectral data. The nephelauxetic ratio (β), covalency ([sgrave]) and bonding (b^½) parameters have been evaluated for the Nd(III) complexes.