Anionic SO₃H-functionalized ionic liquid: An efficient and recyclable catalyst for the Pechmann reaction of phenols with ethyl acetoacetate

ABSTRACT

This paper has reported an anionic SO₃H-functionalized ionic liquid N-methylimidazolium sulfomethylsulfonate ([Hmim][HO₃SCH₂SO₃]) for the synthesis of coumarins by Pechmann reaction. The [Hmim][HO₃SCH₂SO₃] is easier to prepare by one-step neutralization reaction of N-methylimidazole with methanedisulfonic acid and show high catalytic performance for Pechmann reaction. Besides, the catalyst can simply be separated from the reaction mixture and recycled ten times without noticeable loss of activity.

GRAPHICAL ABSTRACT

KEYWORDS:

• Anionic SO₃H-functionalized
• coumarins
• ionic liquid
• Pechmann reaction

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (Project No. 21473225).