Direct Michael addition/decarboxylation reaction catalyzed by a composite of copper ferrite nanoparticles immobilized on microcrystalline cellulose: an eco-friendly approach for constructing 3,4-dihydrocoumarin frameworks

Abstract

Composites of copper ferrite oxide nanoparticles immobilized on microcrystalline cellulose were synthesized and studied for their catalytic activity toward the preparation of novel 3,4-dihydrocoumarin derivatives.

Syntheses, reactivity, and biological applications of coumarins

“…Merging the reactivity of Michael acceptors with decarboxylation of 3-COOH coumarins was also investigated in the eco-friendly approach published by Chowhan and others ( Kumar et al, 2022 ). The authors synthesized a composite of copper ferrite oxide nanoparticles immobilized on microcrystalline cellulose ( 115 , CuFe 2 O 4 @MCC) and studied its catalytic properties for the reactivity of 3-COOH coumarins ( 113 ) against cyclic 1,3-diketones ( 114 ) to construct 3,4-dihydrocoumarin frameworks ( 116 ) ( Scheme 6 — path b ).…”

Visible-light-induced organophotocatalytic and singlet oxygen-initiated domino construction of 1,4-dihydropyridines, C-3 functionalized spiro[indoline-3,4′-pyridines] and C-11 functionalized spiro[indeno-[1,2-b]quinoxaline-11,4′-pyridines]

“…Based on all these aspects and in continuation of our interest in the synthesis of complex heterocyclic compounds, [59][60][61][62][63] here we have demonstrated visible-light-induced transitionmetal-free organophotoredox catalytic domino construction of densely functionalized 1,4-dihydropyridines 5 and 2-amino-3cyano-spiro[indoline-3,4′-pyridines] 7 through a domino multicomponent reaction of aldehydes 1/isatins 6, active methylene compounds 2, dimethyl acetylene dicarboxylates 3, and primary aromatic amines 4 in an aqueous medium at room temperature within a very short reaction time (Scheme 1d). Furthermore, we report herein the first synthesis of fused quinoxaline embedded pyridine scaffolds joined through a quaternary spiro carbon at the C-11 position, namely, 2-amino-3cyano-spiro[indeno [1,2-b]quinoxaline-11,4′-pyridine] derivatives 10 via a visible-light-driven rose bengal catalyzed one-pot domino five-component reaction of 2,2-dihydroxy-1H-indene-1,3(2H)-dione 8, substituted 1,2-diamine 9, malononitrile 2, dimethyl acetylene dicarboxylate 3, and substituted anilines 4 in an aqueous medium at room temperature (Scheme 1d).…”