(478e) β-Pinene Hydrolysis By In-Situ Acid Catalysis In Reversible Smart Solvents

Hallett, J. P., Georgia Institute of Technology
Vinci, D., Georgia Institute of Technology
John, E., Georgia Institute of Technology

Smart solvents are novel materials that can change properties when exposed to certain external stimuli, such as heat, light, or pressure. By simply activating the stimulus, we are able to change the process environment to allow for reaction and then easy separation. We have created a smart molecule with a thermoresponsive on/off switch that enables distinct and rapid property changes. The smart solvent is a reversible, dimethylsulfoxide (DMSO) analog with good dissolution properties for both organic and hydrophilic molecules. The thermoresponsive switch enables conversion of the solvent to highly volatile components that can be separated and recombined easily, creating a closed loop process. We are now using this molecule to facilitate in-situ acid catalyzed reactions. This can be accomplished by using the thermodynamics of our thermoresponsive system, allowing for reversible generation of an in-situ acid. The acid can be eliminated without neutralization by activating the temperature switch, which simultaneously decomposes and separates the acid. We tested this technique on the hydrolysis of Β-pinene, an industrially relevant reaction used for making flavoring chemicals. We compare our results to common industrial methods, such as the use of strong acids, and some recent research with gas-expanded methanol and near-critical water systems. Our results show excellent yields and selectivity toward the desired products, indicating comparable reaction rates to current systems and eliminating wasteful neutralization processes.