trans-Heteroleptic carboxylate-bridged paddlewheel diruthenium(ii, ii) complexes with 2,6-bis(trifluoromethyl)benzoate ligands

Abstract

Carboxylate-ligand substitution reactions of paddlewheel-type diruthenium(II, III) complexes ([Ru^II,III₂(RCO₂)₄]⁺) with 2,6-bis(trifluoromethyl)benzoate (2,6-(CF₃)₂PhCO₂⁻) involving a selective reduction to [Ru^II,II₂] provide a series of trans-substituted paddlewheel-type diruthenium(II, II) complexes, [Ru^II,II₂(2,6-(CF₃)₂PhCO₂)₂(RCO₂)₂(THF)₂] (R = CH₃, 1; C₂H₅, 2; C₃H₇, 3; C₄H₉, 4; C(CH₃)₃, 5; 2,3,5,6-F₄Ph, 6). Crystal structures of 1–6 were determined, and their electronic states were investigated by cyclic voltammetry, density functional theory (DFT) and magnetic measurements. This is the first example of trans-heteroleptic carboxylate-bridged [Ru^II,II₂] complexes.