Syntheses, Reactivity, X-ray Structures, and Antioxidant Properties of Ruthenium(II) Complexes with Aryl/Ferrocenyl-Fluorodithiophosphate Ligands [PPh ₄ ][(X)FPS ₂ ] (X = <i>p</i> -Methoxy-C ₆ H ₄ , <i>p</i

Reaction of Lawesson's reagent analogue precursors with dry potassium fluoride as the fluorinating agent in the presence of tetraphenylphosphonium bromide gave three aryl/ferrocenyl-fluorodithiophosphate ligands [PPh₄][(<i>p</i>-methoxy-C₆H₄)FPS₂] (<b>L1</b>), [PPh₄][(<i>p</i>-ethoxy-C₆H₄)FPS₂] (<b>L2</b>), and [PPh₄][(<i>Fc</i>)FPS₂] (<b>L3</b>) (<i>Fc</i> = Fe(η⁵-C₅H₄)(η⁵-C₅H₅)). The treatment of [(η⁶-<i>p</i>-cymene)RuCl₂]₂ (η⁶-<i>p</i>-cymene = 1-methyl-4-<i>iso</i>-propyl-benzene) with equivalent <b>L1</b> and <b>L3</b> in dichloromethane afforded a binuclear ruthenium(II) complex [(η⁶-<i>p</i>-cymene)Ru{κ²-<i>S</i>,μ-<i>S'</i>-(<i>p</i>-methoxy-C₆H₄)FPS₂}]₂ (<b>1</b>) and a mononuclear ruthenium(II) complex [(η⁶-<i>p</i>-cymene)ClRu{κ²-<i>S</i>,<i>S'</i>-(<i>Fc</i>)FPS₂}] (<b>2</b>), respectively. Interaction of <i>cis</i>-[(phen)₂RuCl₂] (phen = <i>o</i>-phenanthroline) with <b>L1</b> and <b>L2</b> in methanol at reflux gave mononuclear ruthenium(II) complexes <i>trans</i>-[(phen)₂Ru{(κ¹-<i>S</i>-(<i>p</i>-methoxy-C₆H₄)FPS₂)}₂] (<b>3</b>) and <i>trans</i>-[(phen)₂Ru{(κ¹-<i>S</i>-(<i>p</i>-ethoxy-C₆H₄)FPS₂)}₂] (<b>4</b>), respectively. Precursors pre-<b>L1</b>-pre-<b>L3</b>, ligands <b>L1</b>-<b>L3</b>, and ruthenium(II) complexes <b>1</b>-<b>4</b> were well-characterized by IR, NMR, UV-vis, and TOF-MS spectroscopies. The structures of precursor pre-<b>L3</b>, ligands <b>L1</b> and <b>L3</b>, and ruthenium(II) complexes <b>1</b>-<b>4</b> have been established by single-crystal X-ray crystallography. Moreover, the antioxidant properties of ruthenium(II) complexes <b>1</b>-<b>4</b> were evaluated using DPPH free radical and ABTS cation radical-scavenging activities in vitro.