Rhodium‐Catalyzed Dual C−H Activation for Regioselective Triple Annulation of Enaminones: Access to Polycyclic Naphthopyran Derivatives

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(11), P. 1770 - 1776

Published: March 21, 2023

Abstract Rh‐catalyzed C−H activation of arenes for oxidative annulations with alkynes stands out as a protocol polycyclic scaffolds. This perspective drives us to disclose herein rhodium catalyzed regioselective triple annulation enaminones hydroxyl‐alkynoates via double functionalization naphtho‐pyran Secondary coordination OH in alkynoate dictated the regioselectivity. Initial lactonization occurred chemoselectively on enamine part carbo rhodation followed by reductive elimination. was scalable and has shown high functionality tolerance. KIE studies were done get insight mechanism, some downstream transformations achieved show synthetic potential method.

Language: Английский

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Synthesis of Naphtho[1′,2′:4,5]furo[3,2-b]pyridinones via Ir(III)-Catalyzed C6/C5 Dual C–H Functionalization of N-Pyridyl-2-pyridones with Diazonaphthalen-2(1H)-ones

Organic Letters, Journal Year: 2024, Volume and Issue: 26(4), P. 786 - 791

Published: Jan. 22, 2024

Presented herein is an unprecedented synthesis of naphtho[1′,2′:4,5]furo[3,2-b]pyridinones via Ir(III)-catalyzed C6/C5 dual C–H functionalization N-pyridyl-2-pyridones with diazonaphthalen-2(1H)-ones. This protocol forms C–C and C–O bonds in one pot which diazonaphthalen-2(1H)-ones serve as bifunctional reagents, providing both alkyl aryloxy sources. To the best our knowledge, this first example title compounds by using substrates. Notably, method features operational simplicity, good functional group tolerance, high efficiency, atom economy.

Language: Английский

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The “cesium effect” magnified: exceptional chemoselectivity in cesium ion mediated nucleophilic reactions

Chemical Science, Journal Year: 2024, Volume and Issue: 15(14), P. 5277 - 5283

Published: Jan. 1, 2024

Chemodivergent construction of structurally distinct heterocycles from the same precursors by adjusting specific reaction parameters is an emergent area organic synthesis; yet, understanding processes that underpin divergence lacking, preventing development new synthetic methods systematically harnessing key mechanistic effects. We describe herein cesium carbonate-promoted oxadiaza excision cross-coupling reactions β-ketoesters with 1,2,3-triazine 1-oxides form pyridones in good to high yields, instead sole formation pyridines when performed presence other alkali metal carbonates or bases. The can be further extended synthetically challenging pyridylpyridones. A computational study comparing effect and sodium ions reveals cesium-coordinated species changes preference attack at ketone carbonyl ester carbon due ion-specific transition state conformational accommodation, revealing a previously unexplored role may facilitate chemodivergent approaches heterocyclic systems.

Language: Английский

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Pd-catalyzed regioselective rollover dual C–H annulation cascade: facile approach to phenanthrene derivatives

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(64), P. 9714 - 9717

Published: Jan. 1, 2023

A Pd-catalyzed rollover cascade dual C–H annulation of aryl phenols with alkynols for producing phenanthrene scaffolds in a regioselective manner was developed. Necessary control, KIE and deuterium experiments were conducted to determine the reaction mechanism.

Language: Английский

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Co(III)-Catalyzed Regioselective Benzannulation of Substituted Pyridones with 1,6-Diynes via Dual C-H Bond Activation

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(63), P. 8296 - 8299

Published: Jan. 1, 2024

A Co(III)-catalyzed site-selective C5 and C6 benzannulation of substituted pyridones with 1,6-diynes

Language: Английский

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Rh(III)-Catalyzed Weakly Coordinating 2-Pyridone-Directed Oxidative Annulation Using Internal Alkynes: A Reversal in Selectivity

Organic Letters, Journal Year: 2022, Volume and Issue: 24(46), P. 8470 - 8475

Published: Nov. 14, 2022

A rhodium(III)-catalyzed Satoh-Miura type oxidative annulation of N-aryl 2-pyridone derivatives is described using internal alkyne as a coupling partner. weakly coordinating carbonyl group the ring utilized for this transformation. The reaction proceeds with broad scope and wide functional tolerance. solvent plays an important role in developed method to furnish different class annulated product. preliminary investigation was carried out explore photophysical properties obtained polyarylated N-naphthyl 2-pyridones.

Language: Английский

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Pd(II)-Catalyzed Oxidative Naphthylation of 2-Pyridone through N–H/C–H Activation Using Diarylacetylene as an Uncommon Arylating Agent

Organic Letters, Journal Year: 2023, Volume and Issue: 25(11), P. 1952 - 1957

Published: March 10, 2023

A Pd(II)-catalyzed straightforward oxidative naphthylation of unmasked 2-pyridone derivatives is described using a twofold internal alkyne as coupling partner. The reaction proceeds through N–H/C–H activation to provide polyarylated N-naphthyl 2-pyridones. An unusual annulation at the arene C–H bond diarylalkyne leads formation 2-pyridones, where 2-pyridone-attached phenyl ring naphthyl polyaryl-substituted. Mechanistic studies and DFT calculations suggest plausible mechanism based on activation. were studied explore encouraging photophysical properties.

Language: Английский

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Pd(II)‐Catalyzed Selective [4+2] Benzannulations of Pyridones with Alkenes: Diversity‐Oriented Synthesis of a Novel Fluorescent Quinolinone

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 25, 2025

Comprehensive Summary Herein, an intermolecular palladium(II)‐catalyzed regioselective [4+2] benzannulation reaction capable of converting 2‐pyridones into quinolinones was developed using electron‐deficient alkenes as two‐carbon units. An examination the mechanism indicated that extension from 2‐pyridone to quinolinone likely facilitated through a series sequential C—H activation reactions or 6π electrocyclization, culminating in dehydrogenative aromatization. This method diversity‐oriented synthesis derivatives is characterized by broad substrate scope, atom economy, and excellent chemical selectivity. In addition, these exhibit fluorescent absorption within visible‐light spectrum, which makes them suitable candidates for development innovative probes.

Language: Английский

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Co(III)-Catalyzed Three-Component Assembling of 2-Pyridones with Dienes and Formaldehyde via C–H Bond Activation

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 24, 2025

Here, we have demonstrated a Co(III)-catalyzed C–H functionalization of substituted pyridones with dienes and para-formaldehyde via three-component sequential reaction. A library homoallylic alcohols is synthesized high regio- chemoselectivity. The reaction scope widely compatible various N-pyridyl-2-pyridones, butadiene, dienes. Interestingly, N-pyridyl-4-pyridone also participated in the product was further converted into dihydrofuran-derived N-pyridyl-2-pyridone derivatives. convincing mechanism mechanistic investigations are described to justify current methodology.

Language: Английский

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Directing group-assisted selective C–H activation of six-membered N-heterocycles and benzo-fused N-heterocycles

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 11(2), P. 540 - 575

Published: Dec. 7, 2023

Directing group-assisted selective C–H bond activation of six-membered N-heterocycles and benzo-fused has been reported.

Language: Английский

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