One-Pot Synthesis of Substituted Piperidinones and 3,4-Dihydropyrimidinones Using a Highly Active and Recyclable Supported Ionic Liquid Phase Organocatalyst

Abstract

1-Ethyl-3-methylimidazolium ethyl sulfate was synthesized and its supported ionic liquid phase form was prepared and used as an organocatalyst for the synthesis of substituted piperidinones and 3,4-dihydropyrimidinones. The ionic liquid was characterized by 1 H NMR, 13 C NMR, and mass spectrometry. The catalyst is novel, stable, completely heterogeneous, and recyclable for several times and can be easily recovered by filtration. It was characterized with scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and energy-dispersive X-ray spectroscopy techniques. The workup procedures are very simple, and products were obtained in good-to-excellent yields with reasonable purities without the need for further chromatographic purification.

One-pot synthesis of various 2-amino-4H-chromene derivatives using a highly active supported ionic liquid catalyst

“…The product was ltered and crystallized from ethanol if necessary. The products were characterized with 1 H NMR, 13 C NMR and mass spectrometry.…”

“…[6][7][8][9] Recently, ionic liquids are also used as hybrid materials called ionogels well reviewed by Bideau et al 10 Because of considerable and attractive properties of supported ionic liquid catalysis, earlier also we reported the synthesis of various compounds using these catalysts. [11][12][13][14] Here, we intend to design a catalyst combining the homogeneous nature of ionic liquid and palladium having high activity and selectivity with heterogeneous support to provide large interfacial reaction areas. The supported ionic liquid phase catalysis concept is based on a classical homogeneous catalyst that is dissolved in a thin lm of ionic liquid which is further dispersed over the high internal surface of a porous support.…”

“…or13 C NMR data were recorded in CDCl 3 or DMSO-d 6 on Bruker DPX 400 spectrometer. The FTIR spectra were recorded on Perkin-Elmer spectrophotometer and mass spectral data were recorded on Bruker Esquires 3000 (ESI).…”