Structural, magnetic, and 1H NMR spectral study on lantern-type cis- and trans-diruthenium(II,III) complexes with two formamidinato and two acetato bridges

Lantern-type dinuclear complexes, cis-[Ru-2(4-Me-pf)(2)(O2CMe)(2)Cl] and trans-[Ru-2(2,6-Et-2-pf)(2)(O2CMe)(2)Cl] (4-Me-pf(-) = N,N'-bis(4-methylphenyl)formamidinate ion and 2,6-Et-2-pf(-) = N,N'-bis(2,6-diethylphenyl) formamidinate ion), were prepared and characterized. The dinuclear structures with cis- and trans-arrangements of the bridging ligands were confirmed by the X-ray crystal structures as well as H-1 NMR spectra (298 K) in CD2Cl2, where the proton signals were observed at widely spread positions delta = -80 to 25 ppm. Variable-temperature magnetic moments (2-300 K) showed the existence of three unpaired electrons in dinuclear units with large D values (65 cm(-1) for cis-Ru-2(II,III) and 90 cm(-1) for trans-Ru-2(II,III)). (c) 2013 Elsevier B.V. All rights reserved.