New metal catalysts for soybean oil transesterification

We report here the synthesis, characterization, and use of tin (3-hydroxy-2-methyl-4-pyrone)(2)(H2O)(2), lead (3-hydroxy-2-methyl-4-pyrone)(2) (H2O)(2), mercury (3-hydroxy-2-methyl-4-pyrone)(2)-(H2O)(2), and zinc (3-hydroxy-2-methyl-4-pyrone)(2)(H2O)(2) as catalysts in the transesterification reaction of soybean oil with methanol. All complexes are active in this reaction, with the following decreasing activities: Sn2+ much greater than Zn2+ > Pb2+ approximate to Hg2+. The catalytic activities of these complexes were also compared with classical alkali and acid transesterification catalysis (with NaOH and H2SO4).