Mechanism of intermolecular hydroacylation of vinylsilanes catalyzed by a rhodium(I) olefin complex: a DFT study

Theoretical Insight into Ni(0)-Catalyzed Hydroarylation of Alkenes and Arylboronic Acids

The density functional theory (ωB97XD functional) is employed to clarify nickel(0)/P^tBu₃-catalyzed hydroarylation of alkenes and arylboronic acids with methanol. The computational results reveal that this reaction goes primarily through the ligand-to-ligand H transfer from the O-H bond to the alkene coordinated with nickel, complexation of arylboronic acid to the nickel-alkyl-methoxyl intermediate, attack of methoxyl on boron, transmetalation, and reductive elimination. The formation of the branched 1,1-diarylalkane, linear 1,1-diarylalkane, and alkene-dimer is also discussed in this work.

DFT/TDDFT computational study of the structural, electronic and optical properties of rhodium (III) and iridium (III) complexes based on tris-picolinate bidentate ligands

The electronic structures and spectroscopic properties of two complexes [M(pic)₃] (M = Ir, Rh) containing picolinate as bidentate ligands have been calculated by means density functional theory (DFT) and time-dependent DFT/TD-DFT using three hybrid functionals B3LYP, PBE0 and mPW1PW91. The PBE0 and mPW1PW91 functionals, which have the same HF exchange fraction (25%), give similar results and do not differ drastically from B3LYP results. Calculated geometric parameters of the complexes are in good agreement with the available experimental data. The UV absorptions observed in acetonitrile were assigned on the basis of singlet state transitions. The most intense band observed in the UV-C region corresponds to ligand-to-ligand charge transfer states (LLCT) in both complexes. The theoretical spectrum of the rhodium complex is characterized by a large degree of mixing between metal-to-ligand-charge-transfer (MLCT), LLCT and metal centered (MC) states in the UV-A region. The presence of low-lying excited states with MC character affects the absorption spectrum under spin-orbit coupling (SOC) effects and play important roles in the photochemical properties. Graphical abstract Frontier molecular orbital diagram of mer-M(pic)₃ (M=Ir, Rh).

Theoretical investigation of Co(0)-catalyzed intramolecular hydroacylation of 4-pentenal

Density functional theory (DFT) was used to investigate cobalt(0)-catalyzed intramolecular hydroacylation of 4-pentenal. The calculated results indicated the involvement of five possible reaction pathways: the formation of cyclopentanone, cyclobutanone, butylenes, cyclobutane, and cyclopropane, respectively. The former two are pathways of Co(0)-catalyzed intramolecular hydroacylation, while the latter three are pathways of decarbonylation. The formation of cyclopentanone was the most favorable channel, and the oxidative addition reaction of 4-pentenal was the rate-determining step. Hence, the dominant product predicted theoretically was cyclopentanone, which was consistent with experimental results. Solvation had a significant effect, and greatly decreased the free energies of all intermediates and transition states.