Abstract: Disclosed herein are catalytic systems and methods of using the same for preparing a compound comprising an ester group. The catalytic system comprises a first catalyst comprising a metal selected from bismuth, aluminum, titanium, zirconium, and combinations thereof, and a second catalyst comprising titanium, zirconium, and combinations thereof. The method of using the catalytic system for preparing a compound comprising an ester group comprises reacting one or more ester-forming reactants in the presence of the catalytic system under conditions sufficient to prepare the compound comprising the ester group, wherein the one or more ester-forming reactants comprise a compound having a carboxyl group, a hydroxyl group, an anhydride group, or combinations thereof.