Synthesis, characterisation, X-ray crystallography analysis, and thermolysis study of triruthenium carbonyl cluster derivatives of phosphine and arsine ligands

Triruthenium metal carbonyl clusters bearing bidentate and monodentate phosphine/arsine ligands continue to expand as an interesting research area due to their potential application in catalysis as well as its unique bonding modes. However, there is a lack of studies on the structure and the reactivity of Ru₃(CO)₈(µ-L–L)₂ and Ru₃(CO)₉(µ-(L–L))(L) where [L–L = bidentate; L = monodentate phosphine/arsine ligands] complexes involving bidentate diphosphine ligands with more than one methylene group. Most previous research has focused on bidentate ligands with short backbones, such as dppm and dpam, and no crystallographic or thermolysis studies reported for longer chain ligands (dppe, dppp, or dppb) on Ru₃(CO)₈(µ-L–L)₂ and Ru₃ (CO)₉(µ-(L–L))(L) types. This gap limits the understanding of how ligand chain length affects cluster transformation, bonding, and reactivity. It is also fundamentally important to observe the transformation and activation of these ligands on the triruthenium cluster via thermolysis reaction.