Table 3.

ZrOCl₂·8H₂O-catalyzed esterification of propionic acid (1b) with alcohols ^a

^a The reactions were carried out using 5 mmol of acid, 5 mmol of alcohol and 0.025 mmol of ZrOCl₂·8H₂O at r.t. for 24h; ^b The yield in parenthesis was obtained by using the reused catalyst.