A Solvent-free/Effective Base Unsaturated Esters Synthesis using Novel Amine Functionalized Ionic Liquid

Abstract

Abstract: 1-(2-aminoethyl)-3-methylimidazolium bromide [Aemim]Br ionic liquid acted as a catalyst as well as a solvent in the Knoevenagel condensation reaction. The extent of products formed with high yield and more flattering for the synthesis of aliphatic and aromatic esters. The [Aemim] Br can be recycled for 6 runs without great loss of activity. Background: The Knoevenagel condensation was one of the fundamental reactions in organic chemistry both at the laboratory and industrial levels. Objective: An effective method for the condensation of a variety of aliphatic and aromatic carbonyl compounds with ethyl acetoacetate and subsequent hydrolysis to corresponding α, β - unsaturated esters in [Aemim]Br was achieved. Method: The weighed quantity of [Aemim]Br, an aldehyde and ethyl acetoacetate were carried out at 25OC. The reaction commenced instantaneously making the reaction mixture highly viscous. The product was extracted with ether. The combined organic extracts were dried using anhydrous sodium sulphate, evaporated under reduced pressure and assayed on GC. Results: We could achieve to get Knoevenagel condensation with good yield. Conclusion: An effectual procedure for Knoevenagel condensation of a variety of aliphatic and aromatic aldehydes with active ethyl acetoacetate arises smoothly in the presence of [Aemim]Br without any additional solvents. This is the best method that proved an effective green industrial process.