Abstract
Esterification of carboxylic acids and transesterification of β-ketoesters with alcohols have been developed using a catalytic amount of iodine in polyethylene glycol (PEG) ionic liquid (IL 1000) to afford the corresponding esters in good yields. By simple separation of the ionic-liquid phase containing the iodine, the system of I2/IL 1000 can be reused several times.
Notes
a Isolated yields.
b The system of I2/IL 1000 was run for four consecutive cycles.
c IL 400 was used.
d IL 2000 was used.
e IL 4000 was used.
a All reactions were carried out with 3 mol% of iodine in refluxing toluene for 6 h.
b Isolated yields.
a All reactions were carried out with 3 mol% of iodine in refluxing toluene for 6 h.
b Isolated yields.