In Situ Alkylcarbonic Acid Catalysts Formed in CO_2-Expanded Alcohols

摘要

We have developed self-neutralizing acid catalysts formed from carbon dioxide and alcohols for use in chemical synthesis. These alkylcarbonic acid catalysts are generated in situ and can be easily neutralized via depressurization. This technique combines a medium with good organic solubility with acid catalysts that do not require neutralization, thus completely eliminating the solid wastes associated with many acid processes. We examined the origins and characteristics of alkylcarbonic acids by comparing reaction rates of acidsensitive probes in different CO_2-expanded alcohols, elucidating the effect of CO_2 pressure on solvent properties and acid formation, and demonstrating the use of alkylcarbonic acids for a variety of reaction types.