Syntheses, Structure and Magnetic Properties of the First µ1,5‐Dicyanamido‐Bridged Dinuclear Compounds [Ni(µ1,5‐dca)(dca)(dpt)]2 and [Ni(µ1,5‐dca)(dca)(medpt)]2

Abstract

AbstractThe first structural determination of dinuclear compounds with μ1,5‐dicyanamide [dca, N(CN)2−] as bridging ligand has been achieved with the products of formula [Ni(µ1,5‐dca)(dca)(dpt)]2 (1) and [Ni(µ1,5‐dca)(dca)(medpt)]2 (2) [dpt = bis(3‐aminopropyl)amine and medpt = bis(3‐aminopropyl)methylamine]. The X‐ray diffraction analysis reveals dinuclear compounds with double μ1,5‐dicyanamide bridges. The nickel atoms are hexacoordinate. The small differences in the terminal ligand (dpt or medpt) create a drastic change in the magnetic behaviour: the susceptibility measurements of 1 show weak antiferromagnetic coupling (J = −1.2 cm−1, g = 2.29) whereas those of 2 show ferromagnetic coupling (J = 0.7 cm−1, g = 2.17). The related compound (μ‐terephthalato)[Ni(dca)(dpt)(H2O)]2 (3) is also described. The X‐ray diffraction analysis reveals a dinuclear terephthalato‐bridged NiII compound with terminal dca ligands. The susceptibility measurements of 3 indicate weak antiferromagnetic coupling: J = −0.3 cm−1, g = 2.13. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)