A family of edge-sharing bi-octahedral diruthenium(,) compounds containing Ru-Ru single bonds

From paddlewheel starting reactants Ru 2 (R′CO 2 ) 4 + , a family of edge-sharing bi-octahedral (ESBO) diruthenium( iii , iii ) compounds has been prepared, formulated as Ru 2 (μ-O 2 CR′) 2 (μ-OR) 2 (η-L) 2 ( 1-10 ) [R′ = CH 3 , R = CH 3 , L = acac ( 1 ), tfac ( 2 ); R′ = CH 3 , R = CH 2 CH 3 , L = hfac ( 3 ); R′ = CH 2 CH 3 , R = CH 3 , L = acac ( 4 ), tfac ( 5 ); R′ = CH 2 CH 3 , R = CH 2 CH 3 , L = hfac ( 6 ); R′ = CH 2 Cl, R = CH 3 , L = tfac ( 7 ); R′ = CH 2 Cl, R = CH 2 CH 3 , L = hfac ( 8 ); R′ = C 6 H 5 , R = CH 3 , L = tfac ( 9 ); and R′ = H, R = CH 3 , L = acac ( 10 ); here, acac, tfac and hfac represent acetylacetone, trifluoroacetylacetone and hexafluoroacetylacetone, respectively]. Compounds 1-10 have a similar ESBO coordination geometry of the Ru(μ-O 2 CR′) 2 (μ-OR) 2 Ru core with a Ru-Ru center chelated and bridged by two μ-O 2 CR′ and two μ-OR in a trans manner, and each Ru center is also coordinated with a η 2 -L bidentate ligand. The Ru-Ru distances fall in the range of 2.4560(9)-2.4771(4) Å. The investigation of the electronic spectra and vibrational frequencies as well as theoretical studies with density functional theory (DFT) reveal that compounds 1-10 are ESBO bimetallic species of d 5 -d 5 valence electron counts showing a σ 2 π 2 δ 2 δ* 2 π* 2 electronic configuration. Varying -CH 3 to -CF 3 groups on the η 2 -L bidentate ligands coordinating to the Ru(μ-O 2 CR′) 2 (μ-OR) 2 Ru core, and according to Raman spectrum measurements combined with theoretical calculations, the intense bands of compounds 1-10 appearing at ∼345 cm −1 in the small-wavenumber region can be assigned to the stretching of the Ru-Ru single bond. Structural, spectroscopic and theoretical calculation of a family of ESBO diruthenium compounds formulated as Ru 2 (μ-O 2 CR′) 2 (μ-OR) 2 (η-L) 2 ( 1-10 ).