The continuous self aldol condensation of propionaldehyde in supercritical carbon dioxide: a highly selective catalytic route to 2-methylpentenal

The aldol reactions of propionaldehyde and butyraldehyde have been explored in supercritical CO(2), scCO(2), using an automated continuous flow reactor. The reaction was found to proceed over a variety of heterogeneous acidic and basic catalysts and with increased selectivity compared to using neat reactants.