A Phosphine-mediated Synthesis of 2,3,4,5-tetra-substituted Nhydroxypyrroles from α-oximino Ketones and Dialkyl Acetylenedicarboxylates Under Ionic Liquid Green-media

Abstract

In conclusion, ionic liquids are indicated as a useful and novel reaction medium for the selective synthesis of functionalized pyrroles. This reaction medium can replace the use of hazardous organic solvents. Easy work-up, synthesis of polyfunctional compounds, decreased reaction time, having easily available-recyclable ionic liquids, and good to high yields are advantages of present method.

Use of Dialkyl Acetylenedicarboxylates in the Multicomponent Synthesis of Heterocyclic Structures

“…The model reaction was examined using different solvents in which ionic liquid as a green and effective solvent afforded the best result (Scheme 9). [18] Inasmuch as, coumarines and quinolones are typical heterocyles, they exist in many natural products which have biological activities including: antibacterial, antiviral, antimicro- The reaction of 6-aminocoumarin/quino-lones 24, β-nitrostyrenes 25 and dialkyl acetylenedicarboxylate 1 in the presence of 30 mol % of InCl 3 in ethanol under microwave heating condition at 100 °C afforded the corresponding products in good to high yields (Scheme 10). [19] A green and significant approach was developed in 2019 by Balu Atar et al for the synthesis of tetra-substituted pyrrols 27 by utilizing DBAL-2 via the one-pot reaction of dialkyl acetylenedicarboxylate 1, amines 2 and β-nitrostyrene 25 at room temperature under solvent-free condition (Scheme 11).…”

“…The model reaction was examined using different solvents in which ionic liquid as a green and effective solvent afforded the best result (Scheme 9). [18] …”