C–H activation-initiated spiroannulation reactions and their applications in the synthesis of spirocyclic compounds

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(12), P. 2324 - 2338

Published: Jan. 1, 2024

This review summarizes the most recent progress made in C–H bond activation-initiated spiroannulation reactions and their applications construction of structurally diverse biologically valuable spirocyclic scaffolds.

Language: Английский

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Condition-Controlled Selective Synthesis of Pyranone-Tethered Indazoles or Carbazoles through the Cascade Reactions of N-Nitrosoanilines with Iodonium Ylides

Organic Letters, Journal Year: 2023, Volume and Issue: 25(24), P. 4422 - 4428

Published: June 8, 2023

Presented herein is a condition-controlled selective synthesis of pyranone-tethered indazoles or carbazole derivatives via the cascade reactions N-nitrosoanilines with iodonium ylides. Mechanistically, formation former involves an unprecedented process including nitroso group-directed C(sp2)–H bond alkylation N-nitrosoaniline ylide followed by intramolecular C-nucleophilic addition to moiety, solvent-assisted cyclohexanedione ring opening, and transesterification/annulation. On contrary, latter initial annulation denitrosation. These developed protocols feature easily controllable selectivity, mild reaction conditions, clean sustainable oxidant (air), valuable products that are structurally diverse. In addition, utility was showcased their facile diverse transformations into synthetically biologically interesting compounds.

Language: Английский

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Synthesis of 1,7-Fused Indolines Tethered with Spiroindolinone Based on C–H Activation Strategy with Air as a Sustainable Oxidant

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1880 - 1897

Published: Jan. 22, 2024

Herein, we present an efficient synthesis of 1,7-fused indolines tethered with a spiroindolinonyl moiety through the cascade reaction indolin-1-yl(aryl)methanimines diazo oxindoles. To best our knowledge, this is first example in which indoline skeleton was constructed along simultaneous introduction spiro element initiated by C–H bond activation indoline. In forming title product, substrate and coupling partner demonstrated unprecedented pattern latter acts as C1 synthon to participate construction spirocyclic scaffold reductive elimination key seven-membered Ru(II) species using air effective sustainable oxidant regenerate active catalyst. Moreover, studies on cytotoxicity selected products against several human cancer cell lines their potential lead compounds for development anticancer drugs. With notable features such simple economical substrates, pharmaceutically valuable sophisticated skeleton, mild conditions, cost-free oxidants, high efficiency, excellent compatibility diverse functional groups, scalability, method expected find wide applications related areas.

Language: Английский

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Unsymmetrical relay C–H alkenylation and [2 + 2] cycloaddition ofN-arylsydnones with allenyl acetates leading to quinoline-fused cyclobutanes

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(5), P. 1191 - 1197

Published: Jan. 1, 2023

In this paper, we present a direct, effective and atom-economical access toward quinoline-fused cyclobutane derivatives through Rh( iii )-catalyzed cascade reactions of N -arylsydnones with allenyl acetates.

Language: Английский

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Synthesis of Heptacyclic Compounds through C–H Bond Activation-Initiated Cascade Reactions

Organic Letters, Journal Year: 2024, Volume and Issue: 26(35), P. 7425 - 7430

Published: Aug. 22, 2024

Presented herein is an atom- and step-economical method enabling the precise assembly of a heptacyclic scaffold containing both azocine indoline units through cascade reactions indolin-1-yl(aryl)methanimines with diazo indanediones. The formation products involves C–H bond activation double carbene insertion followed by intramolecular condensation, retro-[2 + 2] cycloaddition, recyclization. This reaction not only provided concise straightforward strategy for synthesis otherwise difficult to obtain compounds from readily available substrates but also disclosed unprecedented mode derivatives compounds. In general, this novel synthetic protocol has advantages, such as easily obtainable substrates, structurally sophisticated products, procedure, good compatibility diverse functional groups, ready scalability. Moreover, thus obtained showed decent antiproliferative activity against three human cancer cell lines.

Language: Английский

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Development of novel transition metal-catalyzed synthetic approaches for the synthesis of a dihydrobenzofuran nucleus: a review

RSC Advances, Journal Year: 2024, Volume and Issue: 14(21), P. 14539 - 14581

Published: Jan. 1, 2024

The synthesis of dihydrobenzofuran scaffolds bears pivotal significance in the field medicinal chemistry and organic synthesis. These heterocyclic hold immense prospects owing to their significant pharmaceutical applications as they are extensively employed essential precursors for constructing complex frameworks. Their versatility importance make them an interesting subject study researchers scientific community. While exploring synthesis, have unveiled various novel efficient pathways assembling core. In wake extensive data being continuously reported each year, we outlined recent updates (post 2020) on methodological accomplishments employing catalytic role several transition metals forge functionalities.

Language: Английский

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A divergent construction of fused and bridged carbo-/heterocyclic scaffoldsviacascade reactions of aryl azomethine imines with vinyl cyclic carbonates

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(4), P. 1015 - 1021

Published: Jan. 1, 2023

Presented herein is a divergent synthesis of indene-fused pyrazoles and bridged benzodiazepines tethered with hydroxymethyl group through the cascade reactions aryl azomethine imines vinyl cyclic carbonates.

Language: Английский

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Synthesis of O-Heterocycle Spiro-Fused Cyclopentaquinolinones and Cyclopentaindenes through Visible Light-Induced Radical Cyclization Reactions

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(17), P. 12641 - 12657

Published: Aug. 17, 2023

Presented herein is an effective and sustainable synthesis of O-heterocycle spiro-fused cyclopentaquinolinone cyclopentaindene derivatives through light-driven cascade reactions N-(o-ethynylaryl)acrylamides or 2-(2-(phenylethynyl)benzyl)acrylate with various O-heterocycles. Experimental mechanistic studies revealed that these are initiated by visible light-induced radical formation from its regioselective addition onto the acrylamide acrylate moiety followed 6-exo-dig 5-endo-trig annulation, which terminated single electron oxidation proton elimination. Compared previously reported synthetic methods for similar purposes, this newly developed protocol has advantages such as a broad substrate scope, extremely mild reaction conditions, excellent atom-economy, high efficiency, good compatibility diverse functional groups. With all merits, method expected to find wide applications in related research arena.

Language: Английский

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Ru(ii)-catalyzed regioselective [4 + 1] redox-neutral spirocyclization of aryl amidines with diazopyrazolones: direct access to spiro[indole-3,4′-pyrazol]-5′-ones

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(6), P. 1811 - 1816

Published: Jan. 1, 2024

An efficient protocol to construct spiro[indole-3,4′-pyrazol]-5′-ones via ruthenium( ii )-catalyzed selective C–H bond activation/[4 + 1] spirocyclization starting from easily available N -aryl amidines and diazopyrazolones has been developed.

Language: Английский

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Synthesis of C2-Spiroindolines Based on the Cascade Reaction of 2-Aryl-3H-indoles with Cyclopropanols

Chinese Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 45(2), P. 694 - 694

Published: Jan. 1, 2025

Language: Английский

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