Geochemical transformations of organic compounds take place in water at high temperatures and pressures. These reactions differ greatly from those at ambient conditions owing to a shift from kinetic/enthalpic control to thermodynamic/entropic control. As examples, dehydration of alcohols occurs efficiently even though water is the solvent, and ketones can be made from alkanes with no added reagents.  In these reactions, water acts as solvent, reagent, and catalyst.  In an attempt to provide a predictive understanding of hydrothermal reactions, we have studied model ketones (dibenzylketone, p-methyl dibenzylketone) in H2O at 300�C and 70MPa. We observed reversible interconversion between ketone, alcohol, alkene, and alkane functional groups, in addition to irreversible homolytic C-C and C-H bond cleavage products.  Many products form in water alone, but introducing the minerals Fe2O3, Fe3O4 or FeS results in greater selectivity due to catalysis of specific reaction pathways.

Reaction pathways and mechanisms of ketones in hydrothermal fluids

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.