Aseih Kargar-Dolatabadi - Department of Chemistry, Payame Noor University, P. O. Box ۱۹۳۹۵-۳۶۹۷, Tehran, Iran.
Seyed Sajad Sajadikhah - Department of Chemistry, Payame Noor University, P. O. Box ۱۹۳۹۵-۳۶۹۷, Tehran, Iran
Abdolkarim Zare - Department of Chemistry, Payame Noor University, PO BOX ۱۹۳۹۵-۳۶۹۷, Tehran, Iran
Alemeh Razaghi - Department of Chemistry, Payame Noor University, PO BOX ۱۹۳۹۵-۳۶۹۷, Tehran, Iran

A novel ionic liquid entitled ۳-methyl-۱-sulfonic acid imidazolium mesylate ([Msim][OMs]) was synthesized, and characterized by studying its FT-IR, ۱H NMR, ۱۳C NMR and mass spectra. This ionic liquid was employed as a dual-functional catalyst for the preparation of bis-coumarins via the one-pot pseudo three-component reaction of ۴-hydroxycoumarin (۲ eq.) and arylaldehydes (۱ eq.) under solvent-free and relatively mild conditions. Owing to dual-functionality of [Msim][OMs] (having acidic and basic sites), it could act as a highly effective catalyst for the reaction. Additionally, an attractive mechanism based on dual-functionality of the catalyst was proposed.

Ionic Liquid, ۳-Methyl-۱-sulfonic acid imidazolium mesylate ([Msim][OMs]), Bis-coumarins, Dual-functional catalyst, Solvent-free