Methane CH Activation by Palladium Complexes with
Chelating Bis(NHC) Ligands: A DFT Study
Dominik Munz
Dirk Meyer
Thomas Strassner
10.1021/om400232u.s001
https://acs.figshare.com/articles/journal_contribution/Methane_CH_Activation_by_Palladium_Complexes_with_Chelating_Bis_NHC_Ligands_A_DFT_Study/2402737
Palladium bis(NHC) complexes are
able to catalytically activate
and to promote the oxidation of methane. The conversion of methane
to methyl trifluoroacetate catalyzed by the palladium bis(NHC) complex
dibromido(1,1′-dimethyl-3,3′-methylenediimidazolin-2,2′-ylidene)palladium(II)
was investigated by a DFT study on the B3LYP/6-311++G(d,p)//B3LYP/6-31G(d)
level of theory in combination with solvent and dispersion corrections.
According to the DFT calculations the reaction proceeds by a palladium(II–II–IV)
pathway without formation of palladium(0). A second redox cycle via
a bromide–bromine shuttle, which mediates the oxidation of
palladium(II) to palladium(IV), is proposed. Although CH activation
by palladium(0) is predicted to be a very facile process, this pathway
is very unlikely, due to the extraordinarily high reaction barrier
for reductive elimination. CH activation by palladium(IV) has been
investigated as well and might be a viable pathway comparable in energy
to an activation by palladium(II) with other ligand systems.
2013-06-24 00:00:00
CH activation
DFT
B 3LYP level
palladium
Methane CH Activation
pathway