Base-Promoted Regioselective Annulation of Pyridinium Ylides and Bromoalkynes for the Chemodivergent Synthesis of Indolizines

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 5, 2025

A base-promoted regioselective formal [3 + 2] annulation of pyridinium ylides with bromoalkynes is reported, producing a series substituent-diverse indolizines in generally good yields. mild K2CO3-promoted three-component cyclization and at 2:1 molar ratio delivered C2-acylmethylated indolizines, whereas C2-brominated were generated starting from bearing strong electron-withdrawing groups the unit by using 2,2,6,6-tetramethyl-1-piperidinyloxy as dehydrogenating reagent. The current synthetic methodology offers controllable modular approach to access different substitution patterns, featuring wide substrate scope, functional group compatibility, complete regioselectivity without demand any transition-metal catalysts.

Language: Английский

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Solvent-Regulated Cyclization of Arylidene Isoxazolones with Amidines for Regiodivergent Synthesis of 4- and 5-Acylimidazoles

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 27, 2025

N-Iodosuccinimide-promoted cascade reactions of arylidene isoxazolones with amidines in p-xylene were accomplished, affording 5-acylimidazoles good to excellent yields. Interestingly, when the performed by employing acetonitrile as solvent, 4-acylimidazoles efficiently obtained. Mechanistic studies indicate that formation imidazolyl and acyl moieties may undergo a spiroannulation-ring opening aromatization-hydrolysis reaction sequence. Based on this solvent-regulated tandem strategy, powerful protocol for switchable regiodivergent synthesis structurally diverse was successfully established.

Language: Английский

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Synthesis of Functionalized Indolizines through 1,3-Dipolar Cycloaddition of Zwitterionic Ketenimines and Pyridinium Salts

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 19, 2025

A straightforward and efficient strategy for the synthesis of fully functionalized indolizines has been developed through a transition metal- oxidant-free [3 + 2] cycloaddition reaction zwitterionic ketenimines pyridinium salts. This versatile method proceeds under mild conditions, affording in moderate to good yields. approach involves an intermolecular cycloaddition, followed by enamine/imine tautomerization aromatization. Notably, this demonstrates broad functional group compatibility allows facile scalability, making it valuable tool indolizine-based frameworks organic medicinal chemistry.

Language: Английский

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Green synthesis and anticancer evaluation of dispiroheterocycles containing isatin, tetrahydrobetacarboline, pyrrolidine and aurone motifs

Journal of Molecular Structure, Journal Year: 2024, Volume and Issue: 1321, P. 139870 - 139870

Published: Sept. 1, 2024

Language: Английский

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Iodine-Catalyzed Cascade Annulation of 4-Hydroxycoumarins with Aurones: Access to Spirocyclic Benzofuran–Furocoumarins

Molecules, Journal Year: 2024, Volume and Issue: 29(8), P. 1701 - 1701

Published: April 9, 2024

An attractive approach for the preparation of spirocyclic benzofuran–furocoumarins has been developed through iodine-catalyzed cascade annulation 4-hydroxycoumarins with aurones. The reaction involves Michael addition, iodination, and intramolecular nucleophilic substitution in a one-step process, offers an efficient method easy access to series valuable good yields (up 99%) excellent stereoselectivity. Moreover, this unprecedented protocol provides several advantages, including readily available materials, environmentally benign catalyst, broad substrate scope, simple procedure.

Language: Английский

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