A density functional theory study of the oxidative addition of methyl iodide to square planar [Rh(acac)(P(OPh)3)2] complex and simplified model systems

The transition state for the oxidative addition reaction [Rh(acac)(P(OPh)3)2] + CH3I, as well as two simplified models viz. [Rh(acac)(P(OCH3)3)2] and [Rh(acac)(P(OH)3)2], are calculated with the density functional theory (DFT) at the PW91/TZP level of theory. The full experimental model, as well as the simplified model systems, gives a good account of the experimental Rh-ligand bond lengths of both the rhodium(I) and rhodium(III) β-diketonatobis(triphenylphosphite) complexes. The relative stability of the four possible rhodium(III) reaction products is the same for all the models, with trans-[Rh(acac)(P(OPh)3)2(CH3)(I)] (in agreement with experimental data) as the most stable reaction product. The best agreement between the theoretical and experimental activation parameters was obtained for the full experimental system.

Graphical abstractDensity functional theory calculations of the transition state for the oxidative addition reaction [Rh(acac)(P(OR)3)2] + CH3I (R = Ph, CH3 and H) show that all three model systems give a good account of the experimental Rh-ligand bond lengths of both the rhodium(I) and rhodium(III) β-diketonatobis(triphenylphosphite) complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide