Catalytic Selectivity of Ketalization Versus Transesterification

Selective ketalization of levulinic acid esters (LAE's) provides an industrial pathway for developing novel, renewable building blocks for the synthesis of novel polymers, functional oligomers, polymer additives, and solvents. Using a relatively low amount of moderate to strong protic acid catalyst resulted in selective formation of ketal at > 95% and conversion > 95%, without sacrificing reaction speed. The hydrostability of the ketal-ester was also studied in the presence or absence of strong acid. The ketals showed similar hydrostability compared to an ester and superior hydrostability relative to an anhydride in the absence of strong acid.