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Systematic evaluation of the electronic effect of aluminum-containing ligands in iridium-aluminum and rhodium-aluminum bimetallic complexes.

ABSTRACT: Pyridinemethanolate and oxyquinoline derivatives of previously reported late transition metal-aluminum heterobimetallic complexes containing iridium and rhodium have been synthesized and characterized. A combination of experimental and computational data permits a direct comparison of the electronic effects of each novel aluminum-containing ligand in our library on the late transition metal centers. Alongside electronic data of previously reported oxypyridine bridged systems, we conclude that the addition of a dialkylaluminum(X) (X = anion) fragment does not significantly perturb the electron donor ability of the bridging ligand. Anions bound to the aluminum are also shown to behave similarly. The overall library, thus, suggests that the best predictor of the electron donor ability of an alkylaluminum-containing ligand to a transition metal is the donor power of the bridging ligand.

SUBMITTER: Charles RM

PROVIDER: S-EPMC7530109 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Rhodium and Iridium Complexes of Anionic Thione and Selone Ligands Derived from Anionic N-Heterocyclic Carbenes.

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| S-EPMC9305287 | biostudies-literature

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| S-EPMC4557049 | biostudies-literature

Rhodium and Iridium Mediated C-H and O-H Bond Activation of Two Schiff Base Ligands: Synthesis, Characterization and Catalytic Properties of the Organometallic Complexes.

Project description:Reaction of [Rh(PPh3)3Cl] with two Schiff base ligands, viz. N-(2'-hydroxyphenyl)furan-2-aldimine (H 2 L 1 ) and N-(2'-hydroxyphenyl)thiophene-2-aldimine (H 2 L 2 ), in refluxing toluene affords organorhodium complexes of type [Rh(PPh3)2(L)Cl] (L = L1 and L2). Similar reaction with [Ir(PPh3)3Cl] yields organoiridium complexes of type [Ir(PPh3)2(L) (H)] (L = L1 and L2). Crystal structures of [Rh(PPh3)2(L1)Cl] and [Ir(PPh3)2(L2) (H)] have been determined, where the imine ligands are found to bind to the metal centers as CNO-donors. Structures of [Rh(PPh3)2(L2)Cl] and [Ir(PPh3)2(L1) (H)] have been optimized by density functional theory method. Formation of the organometallic complexes is believed to proceed via C-H and O-H bond activation of the imine ligands. All four complexes show intense absorptions in the visible and ultraviolet regions. Cyclic voltammetry on the complexes shows an oxidation on the positive side of SCE and a reduction on the negative side. The organoiridium complexes are found to efficiently catalyze Suzuki-type C-C cross coupling reactions.

| S-EPMC8380818 | biostudies-literature

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