Divergent synthesis of fused N-heterocyclesviarhodium-catalysed [4 + 2] cyclization of pyrazolidinones with iodonium ylides

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(8), P. 2181 - 2186

Published: Jan. 1, 2022

We developed a catalytic system-controlled tunable strategy for the divergent synthesis of cinnolines and pyrazolo[1,2- ]cinnolines via rhodium-catalyzed [4 + 2] cyclization easily available pyrazolidinones iodonium ylides.

Language: Английский

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Enantioselective Synthesis of Indole-Fused Polycycles Bearing Four Consecutive Stereocenters via Rhodium Catalysis

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

Published: Feb. 3, 2025

Indole-fused polycycles are common in natural products and bioactive molecules, yet their concise efficient synthesis remains challenging, especially for compounds with multiple stereocenters. Herein, we report the application of a chiral CpxRhIII catalyst enantioselective C–H activation/[4+2] annulation indoles bicyclic alkenes. This catalytic system exhibits high enantioselectivity broad functional group tolerance operates under benign conditions. The scope this methodology encompasses variety substrates, delivering novel polycyclic four consecutive stereocenters bridged ring good to excellent yields remarkable enantioselectivities (≤1:99 er). approach facilitates structurally diverse molecules that retain integrity while introducing chirality. More importantly, 3ab significantly inhibited proliferation CESS Kasumin-1 cells IC50 values 0.76 0.28 μM, respectively. In addition, has been demonstrated as an effective agent promoting apoptosis cells.

Language: Английский

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Selective Synthesis of Pyrazolonyl Spirodihydroquinolines or Pyrazolonyl Spiroindolines under Aerobic or Anaerobic Conditions

Organic Letters, Journal Year: 2022, Volume and Issue: 24(51), P. 9473 - 9478

Published: Dec. 16, 2022

Presented herein is a condition-controlled selective synthesis of pyrazolonyl spirodihydroquinolines or spiroindolines through formal [5 + 1] [4 spiroannulation 2-alkenylanilines with diazopyrazolones. Mechanistically, the formation title products involves initial generation spiro-fused seven-membered ruthenacycle species serving as key intermediate Ru(II)-catalyzed C-H/N-H bonds metalation, carbene formation, and its migratory insertion. When reaction carried out under air, undergoes reductive elimination to afford spirodihydroquinoline. run argon, protonation intramolecular nucleophilic addition furnish spiroindoline. This work provides an atom-economical protocol for effective functionalization alkenyl C(sp2)-H bond, allowing rapid assembly valuable spiroscaffolds broad range substrates.

Language: Английский

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Rh(iii)-catalyzed simultaneous [3 + 3]/[5 + 1] annulation of 1-arylpyrazolidinones withgem-difluorocyclopropenes leading to fluorinated pyridopyrimidinone derivatives

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(21), P. 5976 - 5982

Published: Jan. 1, 2022

Presented herein is an efficient and concise synthesis of fluorinated pyridopyrimidinone derivatives through formal [3 + 3]/[5 1] annulation 1-arylpyrazolidinones with gem -difluorocyclopropenes.

Language: Английский

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Coupling partner-dependent unsymmetrical C–H functionalization of N-phenoxyacetamides leading to sophisticated spirocyclic scaffolds

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(17), P. 4583 - 4590

Published: Jan. 1, 2022

In this paper, a coupling partner-dependent unsymmetrical C–H functionalization of N -phenoxyacetamides leading to the formation sophisticated spirocyclic scaffolds is presented.

Language: Английский

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Catalyst-Controlled Switchable (5 + 4)/(3 + 4) Cycloadditions for the Divergent Synthesis of Pyrazole-Fused Seven- and Nine-Membered Heterocycles

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(16), P. 10694 - 10704

Published: Aug. 1, 2023

Developing diversity-oriented synthetic approaches for medium-sized rings is of great interest, and the divergent synthesis with different ring sizes poses a challenging task. In this study, we present catalyst-controlled switchable (5 + 4)/(3 4) cycloaddition strategy seven- nine-membered heterocycles. Utilizing two 4-aminopyridine Lewis base catalysts, pyrazole-fused benzazepines or benzoxazonines can be efficiently assembled from same substrates. These products exhibit good stability without interconversion under reaction conditions elevated temperatures. The origin chemoselectivity was elucidated by means computational studies involving DFT calculations, distortion/interaction analysis, noncovalent interaction analysis.

Language: Английский

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Rh(III)-Catalyzed Successive C–H Activations of 2-Phenyl-3H-indoles and Cyclization Cascades to Construct Highly Fused Indole Heteropolycycles

Organic Letters, Journal Year: 2023, Volume and Issue: 25(19), P. 3341 - 3346

Published: May 5, 2023

Rh(III)-catalyzed successive C-H activations of 2-phenyl-3H-indoles and cyclization cascades with diazo compounds were developed to construct highly fused indole heteropolycycles a broad range substrates good yields. In particular, this transformation included two unusual [3+3] [4+2] sequential cascades, in which the compound played different role processes, while simultaneously forming polycyclic scaffold new quaternary carbon center.

Language: Английский

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Construction of Vinyl‐SubstitutedN‐HeterocyclesviaRh(III)‐Catalyzed C−H Functionalization/Annulation of Pyrazolidinones

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(2), P. 238 - 243

Published: Jan. 5, 2023

Abstract The transition‐metal‐catalyzed C−H activation and annulation reactions of pyrazolidinones with 4‐vinyl‐1,3‐dioxolan‐2‐one or vinylene carbonate are described herein. This protocol provided two types pyrazolo[1,2‐a]cinnolines as essential assets for the development bioactive compounds, synthetic practicality was performed explained 44 examples. possible mechanism these is proposed based on preliminary studies previous reports, no oxidant added to both reactions. magnified image

Language: Английский

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Rh(III)-Catalyzed Synthesis of Substituted Isoindoles through a Direct C–H Activation/[4 + 1] Annulation and Acyl Migration Cascade of Oxadiazolones with Diazo Compounds

Organic Letters, Journal Year: 2023, Volume and Issue: 25(18), P. 3195 - 3199

Published: May 1, 2023

A Rh(III)-catalyzed C-H bond activation for the synthesis of fused 2H-isoindole scaffolds from oxadiazolones with diazo compounds was developed. The reaction proceeded through oxadiazolones/[4 + 1] annulation, intramolecular cyclization, and an unusual acyl migration cascade to afford target good yields. These derivatives could be further transformed into intriguing drug privileged scaffolds.

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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