Intercalation-induced Esterification over a Layered Transition Metal Oxide

摘要

The layered transition metal oxide HNbMoO6 is demonstrated to catalyze the esterification of lactic acid (a hydroxycarboxylic acid) with activity superior or comparable to conventional ion-exchange resins. Layered HNbMoO6 also catalyzes the esterification of propionic acid (a carboxylic acid) in the presence of lactic acid, despite exhibiting negligible activity for any carboxylic acid as the sole reactant. X-ray diffraction (XRD) measurements indicate that lactic acid is intercalated into the interlayer structure of the oxide whereas carboxylic acid is not. The intercalation mechanism thus greatly affects the catalytic activity of this layered catalyst.