Efficient C-C Bond Formation between Two Levulinic Acid Molecules To Produce C-10 Compounds with the Cooperation Effect of Lewis and Bronsted Acids

An original route for levulinic acid (LA) conversion was achieved via C-C bond formation in a co-catalysis system containing Lewis and Bronsted acids. Different from conventional base-catalyzed processes, this acidic reaction system inhibits the carboxylic acid from deactivating the base catalyst, additionally simplifies the technical processes. The synergistic effect of the two types of acids effeciently catalyzed the dimerization reaction of LA to generate two C-10 compounds, tetrahydro-2-methyl-5,gamma-dioxo-2-furanpentanoic acid and 3-(2-methyl-5-oxo-tetrahydrofuran-2-yl)-4-oxopentanoic acid, with the total yield of 50.9% at 59.7% conversion. These products present high added value as fuel or fine chemical precursors.