Various room temperature ionic liquids (RTILs), notably, 1-methoxyethyl-3-methylimidazolium trifluoroacetate [MeOEtMIM]+[CF3COO]ˉ , have been used to promote the Knoevenagel condensation to afford substituted olefins. All reactions proceeded effectively in the absence of any other catalysts or co-solvents with good to excellent yields. This method is simple and applicable to reactions involving a wide range of aldehydes and ketones with methylene compounds. The ionic liquid can be recycled without noticeable reduction of its catalytic activity. A plausible reaction mechanism is proposed.
Bibliographical noteThe published manuscript is available at EurekaSelect via http://www.eurekaselect.com/openurl/content.php?genre=article&doi=10.2174/1570179412666150505185134
- Carbonyl compounds
- Ionic liquids
- Knoevenagel condensation
Hu, X., Ngwa, C., & Zheng, Q. (2016). A simple and efficient procedure for Knoevenagel reaction promoted by imidazolium-based ionic liquids. Current Organic Synthesis, 13(1), 101-110. https://doi.org/10.2174/1570179412666150505185134