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Bonding and Reactivity of a Pair of Neutral and Cationic Heterobimetallic RuZn₂ Complexes.

ABSTRACT: A combined experimental and computational study of the structure and reactivity of two [RuZn₂Me₂] complexes, neutral [Ru(PPh₃)(Ph₂PC₆H₄)₂(ZnMe)₂] (2) and cationic [Ru(PPh₃)₂(Ph₂PC₆H₄)(ZnMe)₂][BAr^F₄] ([BAr^F₄] = [B{3,5-(CF₃)₂C₆H₃}₄]) (3), is presented. Structural and computational analyses indicate these complexes are best formulated as containing discrete ZnMe ligands in which direct Ru-Zn bonding is complemented by weaker Zn···Zn interactions. The latter are stronger in 2, and both complexes exhibit an additional Zn···C_aryl interaction with a cyclometalated phosphine ligand, this being stronger in 3. Both 2 and 3 show diverse reactivity under thermolysis and with Lewis bases (PⁿBu₃, PCy₃, and IMes). With 3, all three Lewis bases result in the loss of [ZnMe]⁺. In contrast, 2 undergoes PPh₃ substitution with PⁿBu₃, but with IMes, loss of ZnMe₂ occurs to form [Ru(PPh₃)(C₆H₄PPh₂)(C₆H₄PPhC₆H₄Zn(IMes))H] (7). The reaction of 3 with H₂ affords the cationic trihydride complex [Ru(PPh₃)₂(ZnMe)₂(H)₃][BAr^F₄] (12). Computational analyses indicate that both 12 and 7 feature bridging hydrides that are biased toward Ru over Zn.

SUBMITTER: Miloserdov FM

PROVIDER: S-EPMC8730504 | biostudies-literature |

REPOSITORIES: biostudies-literature

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