Abstract
A novel task-specific ionic liquid, 2-carboxy-
N
,
N
-diethylethanaminium acetate denoted as [Et
2
NH(CH
2
)
2
CO
2
H][AcO], is prepared in an easy process and fully characterized by using suitable methods such as FT-IR,
1
H-NMR,
13
C-NMR, and TG, DTG and DTA analyses. After preparation, the promoting ability of this catalyst for one-pot multicomponent synthesis of 2-amino-4
H
-chromenes, dihydropyrano[3,2-
c
]chromenes and dihydropyrano[2,3-
c
]pyrazoles using in situ-developed arylidenemalononitriles through Knoevenagel reaction under solvent-free conditions is described. The sustainable procedure, short reaction times (6–36 min), effortless work-up, non-chromatographic purification, good-to-excellent product yields (79–96%), ease of recovery and reusability of the catalyst up to six reaction runs without a decrease of activity are the notable features of the present protocol.