Polynuclear Chain Compound of Tetrakis(μ-n-butyrato-O,O′)diruthenium Bromide

Abstract

The title compound of [Ru₂(O₂CCH₂CH₂CH₃)₄Br]_n was prepared and the crystal structure was determined by the single-crystal X-ray diffraction method at 90 K. It crystallizes in the tetragonal space group I42d with a = 13.2222(10)Å, c = 24.0779(18)Å, V = 4209.5(7)ų, D_x = 1.990 g/cm³, and Z = 8. The R1 [I > 2σ(I)] and wR2 (all data) values are 0.0310 and 0.0572, respectively, for all 2430 independent reflections. The two ruthenium atoms are bridged by four n-butyrato ligands in the syn-syn mode with the Ru–Ru distance of 2.2897(9)Å. Both of the axial sites of the dinuclear ruthenium units are bridged by bromido ligands with the Ru–Br distance of 2.7078(7)Å to form an alternated zig-zag chain molecule with Ru–Ru–Br and Ru–Br–Ru angles of 172.68(2) and 117.21(3)°, repectively. The temperature-dependent profile of the magnetic moment was simulated with g = 2.14, D = 67 cm⁻¹, zJ = 0.38 cm⁻¹ values. The g and D values are similar to those of other tetracarboxylato Ru₂⁵⁺ complexes.