Abstract
An environmentally benign, stable yet efficient organocatalyst is highly desirable from the viewpoint of green chemistry and catalysis. Imidazole-based zwitterionic-type molten salts are a new type of organocatalysts with high catalytic application in various organic transformations with added advantage of room temperature ionic liquid (RTIL) property. Most importantly, these ionic-liquid catalysts are easily recyclable and subsequently reusable for multiple times without loss of significant catalytic efficiency. It has also been evident that C2–H of the imidazole has a vital role in catalyzing the reaction via electrophilic activation. Moreover, by changing the cations and/or anions, the properties of ILs can be tuned in many ways. In this article, the role of imidazolium zwitterionic molten salts as an organocatalyst for selective organic transformations including syn-selective aza-Henry reaction, Erlenmeyer reaction, synthesis of different heterocycles and their functionalization and regioselective ring-opening reactions has been elaborated chronically which will definitely be helping to the readers to explore this new class of organocatalyst for further applications.
Funding source: Council of Scientific and Industrial Research
Award Identifier / Grant number: 02(0455)/21/EMR-II
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: This work was financially support from CSIR, New Delhi (Grant no. 02(0455)/21/EMR-II).
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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