Perfluorinated Sulfonate Resins as Reusable Heterogeneous Catalysts for the One-Pot Synthesis of DiPhenolic Esters (DPEs)

Levulinic acid, easily obtained from cellulose, represents a fundamental chemical platform for a number of valuable building blocks. Among them, diphenolic acid and its esters (DPA and DPE) are valid candidates to replace Bisphenol A in polycarbonate and epoxy resin production processes. In this study, we report a one-pot synthesis of alkyl DPEs in the presence of a heterogenous acid catalyst starting from levulinic acid, an alcohol and phenol as solvent-reagent. The most interesting member of the DPE family, the ethyl 4,4-bis(4-hydroxyphenyl)pentanoate, is selectively obtained in a good yield in the presence of a commercially available heterogeneous acid catalyst, the Aquivion, which can be reused for at least six times without any noticeable loss in activity.