Novel Ionic Liquid with Both Lewis and Brønsted Acid Sites for

Abstract: Ionic liquid with both Lewis and Bronsted acid sites has been synthesized and its catalytic activities for Michael addition were carefully studied. The novel ionic liquid was stable to water and could be used in aqueous solution. The molar ratio of the Lewis and Bronsted acid sites could be adjusted to match different reactions. The results showed that the novel ionic liquid was very efficient for Michael addition with good to excellent yields within several min. Operational simplicity, high stability to water and air, small amount used, low cost of the catalyst used, high yields, chemoselectivity, applicability to large-scale reactions and reusability are the key features of this methodology, which indicated that this novel ionic liquid also holds great potential for environmentally friendly processes. Keywords: novel ionic liquid; Michael addition; Lewis and Bronsted acid sites 1. Introduction Acid catalysts are very important in chemical industries for the production of various chemicals [1]. Chloride and sulfonic alkyl groups functionalized ionic liquids were reported as environmentally friendly acidic catalysts due to the combination of the advantages of liquid and solid acids, e.g.,