Recent Advances on Synthesis of 2H‐Chromenes, and Chromenes Fused Hetrocyclic Compounds

Asian Journal of Organic Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Июль 12, 2024

Abstract Chromenes and 2H ‐Chromenes are vital components of natural products, pharmaceuticals, agrochemicals that have captured the attention researchers worldwide. These heterocyclic compounds represent an essential class structural scaffolds, quest for their synthesis in a mild straightforward way has gained significant momentum. oxygen‐containing heterocycles been widely studied due to potential medicinal properties. In last two decades, made remarkable progress towards chromene based using O‐propargylated benzaldehydes as substrate. substrates highly versatile contain functional groups make them ideal wide range reactions. This review article provides in‐depth analysis latest advances alkynes’ functionalization, emphasizing substrate scope, limitations, regioselectivity control, applications these The also covers critical methods strategies, including multicomponent reactions, used general numerous types derivatives.

Язык: Английский

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Construction of Diverse Fused Chromene Frameworks via Isocyanide-Based Three-Component Reaction

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 10854 - 10866

Опубликована: Июль 12, 2024

A convenient synthetic protocol for diverse fused chromenes was successfully developed by a three-component reaction of alkyl isocyanides, dialkyl but-2-ynedioates, and various cyclic 1,3-dipolarophiles containing

Язык: Английский

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Base-Mediated Synthesis of Imidazole-Fused 1,4-Benzoxazepines via 7-exo-dig Cyclizations: Propargyl Group Transformation

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 26, 2025

Herein, we describe the synthesis of a series imidazole-fused 1,4-benzoxazepines using 7-exo-dig cyclizations. Two sets substrates, one containing disubstituted alkyne functional groups and other featuring terminal alkynes, were synthesized by O-propargylation, Sonogashira cross-coupling, condensation reactions between aldehydes o-diaminobenzene. While substrates yielded exocyclic E/Z configured cyclization products smoothly, involving alkynes resulted in formation isomeric with altered skeletal structures, addition to expected products. Density theory (DFT) calculations used clarify mechanisms underlying these It is suggested that unexpected are formed through intermolecular O-to-N-propargyl transfer reactions, followed cyclization, accordance Baldwin's rules. Furthermore, this study extensively demonstrates conversion endocyclic base-mediated 1,3-H shift.

Язык: Английский

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One-Pot, Two-Step Synthesis of Highly Functionalized 4-Indolyl/Pyrrolyl-Chromanes via para-Quinone Methide Formation-1,8-Addition Sequence

Synthesis, Год журнала: 2024, Номер unknown

Опубликована: Июль 23, 2024

Abstract An efficient one-pot, two-step synthesis of structurally diverse 4-indolyl-/pyrrolyl-chromanes was developed starting from o-propargylated salicylaldehydes, 2,6-dialkylphenols and indoles/pyrrole. This process begins with a sequential secondary amine-catalyzed formation p-quinone methides followed by Brønsted acid catalyzed 1,8-addition indoles/pyrrole to access the functionalized chromanes in high yields (up 91%). reaction generates three new C–C bonds, shows step- atom-economy only one molecule water as side product gives complex molecular frameworks without need for isolation intermediates.

Язык: Английский

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Bis(2-cyanoacetamide) in Heterocyclic Synthesis: Synthesis of Some Bis[2-oxopyridine, 2-iminochromene, Chromeno[3,4-c]pyridine, Benzochromeno[3,4-c]pyridine] Derivatives

Oriental Journal Of Chemistry, Год журнала: 2024, Номер 40(1), С. 65 - 73

Опубликована: Фев. 25, 2024

N,N'-(methylenebis(1,4-phenylene))bis-(2-cyanoacetamide) was exploited as a precursor for synthesing some bis (benzylidene 5a-c, pyridines 7, 8, 10a,b, chromene 14, benzochromene 15) derivatives containing diphenyl-methylene spacer via the reaction with each of aromatic aldehydes, pentane-2,4-dione, acetaldehyde/ malononitrile, arylidene-malononitriles, ethyl cinnamates, 2-hydroxybenzaldehyde, and 2-hydroxy-1-naphthaldehyde). Bis(chromeno[3,4-c]pyridines 16&18) were synthesized Michael's addition malononitrile or cyanoacetate to bis(chromene) derivative. The newly prepared compound structures established ir, NMR spectroscopic data.

Язык: Английский

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Six-membered ring systems: With O and/or S atoms

Progress in heterocyclic chemistry, Год журнала: 2024, Номер unknown, С. 421 - 484

Опубликована: Янв. 1, 2024

Язык: Английский

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