Jump to main content
Jump to site search


Theoretical study of aromatic hydroxylation of the [Cu2(H-XYL)O2]2+ complex mediated by a side-on peroxo dicopper core and Cu-ligand effects

Author affiliations

Abstract

In this work, the aromatic hydroxylation mechanism of the [Cu2(H-XYL)O2]2+ complex mediated by a peroxo dicopper core and Cu-ligand effects are investigated by using hybrid density functional theory (DFT) and the broken symmetry B3LYP method. Based on the calculated free-energy profiles, we proposed two available mechanisms. The first reaction steps of both mechanisms involve concerted O–O bond cleavage and C–O bond formation and the second step involves the Wagner–Meerwein rearrangement of the substrate by a [1,2] H shift (HA shift from CA to CC) or (HA shift from CA to OA) across the phenyl ring to form stable dienone intermediates, and this is followed by the protonation of bridging oxygen atoms to produce the final hydroxylated dicopper(II) product. The HA shift from CA to CC mechanism is the energetically most favorable, in which the first reaction step is the rate-limiting reaction, with a calculated free-energy barrier of 19.0 kcal mol−1 and a deuterium kinetic isotope effect of 1.0, in agreement with experimental observations. The calculation also shows that the reaction started from the P-type species of [Cu2(H-XYL)O2]2+ which is capable of mediating the direct hydroxylation of aromatic substrates without the intermediacy of an O-type species. Finally, we designed some new complexes with different Cu-ligands and found the complex that computationally possesses a higher activity in mediating the hydroxylation of the ligand based aromatic substrate; here, Cu loses a pyridyl ligand donor by dissociation, compared to the [Cu2(H-XYL)O2]2+ complex.

Graphical abstract: Theoretical study of aromatic hydroxylation of the [Cu2(H-XYL)O2]2+ complex mediated by a side-on peroxo dicopper core and Cu-ligand effects

Back to tab navigation

Supplementary files

Publication details

The article was received on 07 Jul 2019, accepted on 30 Sep 2019 and first published on 01 Oct 2019


Article type: Paper
DOI: 10.1039/C9DT02814E
Dalton Trans., 2019, Advance Article

  •   Request permissions

    Theoretical study of aromatic hydroxylation of the [Cu2(H-XYL)O2]2+ complex mediated by a side-on peroxo dicopper core and Cu-ligand effects

    Y. F. Liu, J. Shen, S. Chen, W. Qiao, S. Zhou and K. Hong, Dalton Trans., 2019, Advance Article , DOI: 10.1039/C9DT02814E

Search articles by author

Spotlight

Advertisements