Synergistic Effects of Cyclic Ketals in Fuel Compositions and Antibacterial Agents.

A synergistic effect of cyclic ketals in compositions with lower alcohols has been revealed for the first time while adding those ketals to alcohol-containing gasoline. By using model oxidation reactions of ketals and their structural analogs, 1,3-benzodioxolanes, in protic media, the synergistic effect was rationalized assuming the formation of ketal–alcohol complexes possessing surfactant properties, which give rise to hydrated supramolecular structures around them. Deactivation of hot radicals with the transition from the explosive combustion mode to stationary combustion inside these structures is more effective than in the bulk medium. Such structuring effect is general for the behavior of ketals in hydrophobic–hydrophilic systems, including biological ones. This conclusion has been confirmed by studying the activity of cyclic ketals in compositions with antibacterial agents, as well as with alcohols and carboxylic acids. [ABSTRACT FROM AUTHOR]