Gas phase fragmentation of η2 coordinated aldehydes in [VO2(η2-OCHR)]-: Aldehyde structure dictates the nature of the products

Abstract

The gas phase fragmentation reactions of η2 coordinated aldehydes in [VO2(η2-OCHR)]-, which have previously been shown to play a role in the catalytic oxidation of alcohols to aldehydes, were examined using a combination of isotope labelling experiments and collision induced dissociation in a quadrupole ion trap mass spectrometer. The experimental data were interpreted with the aid of density functional theory calculations (DFT). The types of fragmentation reactions observed depend on the nature of the R group. When R = H, the dominant fragmentation channel involves formation of [VO2H2]-via loss of CO. Minor losses of H2 and CH2O are also observed. When R = Me, loss of H2 is observed to give..