Oxygen atom transfer reactions in inorganic analogues of the active site of dimethyl sulfoxide reductase; a DFT and ONIOM (DFT:PM3) study

Abstract

Both density functional theory (DFT) and dual level (ONIOM) calculations have been used to explore the electronic structure and reactivity of dithiolene complexes of molybdenum and tungsten involved in oxygen transfer reactions in which dimethyl sulfoxide is reduced to dimethyl sulfide. The DFT calculations predict both a reaction profile and the effect of substituents on the axial phenyl ligand in line with experiment. ONIOM calculations in which the axial phenyl group is described at the PM3 level are also successful in describing these features, although the PM3 method is unsuitable for describing the reaction without reparameterization. It is shown that new molybdenum parameters can be developed by calibration against experimental and theoretical data for the photoionization of species containing the [MoOS₄]¹⁻ centre.

Acknowledgements

We thank IBM (UK) and EPSRC for support of this research and Professor C.D. Garner for helpful discussion.