Lithium Chloride–Assisted Selective Hydrolysis of Methyl Esters Under Microwave Irradiation

Abstract

A rapid and mild method for the selective hydrolysis of methyl ester in lithium chloride–N,N-dimethylformamide (LiCl–DMF) system under microwave irradiation has been developed. The effects of substituent, metal salt, and solvent on the reactivity and selectivity of the hydrolysis reaction have been investigated. Microwave irradiation significantly improves the reaction yield within a short time in an LiCl–DMF system. Moreover, the chiral α-carbon of methyl esters retained its configuration during the reaction. Finally, the catalytic mechanism of hydrolysis by LiCl salt has also been proposed.

Keywords:

• N,N-Dimethylformamide
• hydrolysis
• lithium chloride
• methyl esters
• microwave irradiation

Notes

^a The hydrolysis of methyl esters carried out at 545 W for 10 min of irradiation.

^b Substrate/salt/solvent = 1: 5: 5 mmol.

^a The hydrolysis of methyl esters was carried out at 545 W for 10 min of irradiation, using DMF as solvent.

^b Substrate/salt/solvent = 1:5:5 mmol.

Notes. The methyl ester esterolysis reactions were carried out at 545 W for 10 min of irradiation in the LiCl–DMF system, Substrate/salt/solvent = 1:5:5.

Notes. The methyl ester esterolysis reactions were carried out at 545 W for 10 min of irradiation in the LiCl–DMF system, Substrate/salt/solvent = 1:5:5.