Interaction of Chromocene with MgO and Reactivity of the Adsorbed Species Towards CO - an IR Study

The interaction of chromocene with partially and totally dehydroxylated MgO and the reactivity of the adsorbed species towards CO have been studied by IR spectroscopy. Cp2Cr is weakly adsorbed on residual surface MgOH groups, forming hydrogen bonded species and, on the extended (100) faces, forming clustered (Cp2Cr)n species. A stronger interaction is observed with the highly unsaturated ions located on the edges and comers of the MgO microcrystals. Upon dosage of CO at room temperature, Cp2CrCO complexes are formed which are stabilized by interaction with the Mg2+ and O2- ions of the surface. The occurrence of an activated process leading to [Cp2Cr]+ and [CpCr(CO)3]- charged reaction products is also observed.