Divergent Synthesis of [3,4]-Fused 3-Alkenyl-Oxindoles via Propargyl Alcohol-Triggered C(sp³)–H Functionalization

ACS Catalysis, Journal Year: 2021, Volume and Issue: 12(2), P. 943 - 952

Published: Dec. 30, 2021

[3,4]-Fused oxindoles are the core structures of naturally occurring oxindole alkaloids, and fused tricyclic have distinguished themselves with unique biological activities. Herein, we developed a synthetic strategy for divergent synthesis diverse types [3,4]-seven- or six-membered ring-fused 3-alkenyl-oxindoles incorporating benzazepine significant building blocks from propargyl alcohols via cascade nucleophilic substitution/site-selective hydride transfer/cyclization process unprecedentedly. In addition, variety nucleophiles, including H2O, were available controllable construction wide range conjugated alkenes, ketones, allyl encompassing natural products pharmaceutical motifs utilization 4-amine substituted isatins widespread terminal alkyne-derived alcohols. Furthermore, utility methodology mechanistic studies also well presented.

Language: Английский

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Metal-Catalyst-Free Radical Cyclization of 1,6-Enynes for the Selective and Switchable Synthesis of Lactams in Water

ACS Sustainable Chemistry & Engineering, Journal Year: 2022, Volume and Issue: 10(18), P. 6057 - 6062

Published: April 27, 2022

Three types of novel radical cyclization 1,6-enynes with sulfonyl hydrazides have been presented, which provided convenient synthetic approaches for accessing five-membered cyclic lactams, lactams containing C–I bond, and six-membered lactams. Notably, these transformations are implemented in metal-catalyst-free systems, three classes important lactam derivatives were synthesized selectivity controllability from the same substrate using water as green solvent.

Language: Английский

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Merging dearomatization with redox-neutral C(sp³)–H functionalization via hydride transfer/cyclization: recent advances and perspectives

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(18), P. 5041 - 5052

Published: Jan. 1, 2022

This review highlights the encouraging advances in hydride transfer-involved dearomatization reaction during past decade, content of which is categorized according to acceptors, namely vinylogous imines and quinone methides.

Language: Английский

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Controllable Synthesis of N-Heterocycles via Hydride Transfer Strategy-Enabled Formal [5 + 1] and [5 + 2] Cyclizations

Organic Letters, Journal Year: 2023, Volume and Issue: 26(1), P. 332 - 337

Published: Dec. 28, 2023

The Brønsted acid-controlled switchable synthesis of indoline-fused tetrahydroquinolines and indole-fused benzazepines was developed through hydride transfer-enabled formal [5 + 1] 2] cyclization reactions from indoles N-alkyl o-aminobenzoketones. Indoline, furanone, tetrahydroquinoline hybridized pentacyclic products were unprecedentedly accessed via a cascade condensation/hydride transfer/dearomatization-cyclization/deethylation/nucleophilic addition process. In addition, the undeveloped transfer-involved cyclizations also realized for direct construction benzazepines.

Language: Английский

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Divergent synthesis of nitrogen heterocyclesviaH₂O-mediated hydride transfer reactions

Green Chemistry, Journal Year: 2023, Volume and Issue: 25(13), P. 5134 - 5141

Published: Jan. 1, 2023

The H 2 O-promoted controllable synthesis of diverse 3-carboxyl and 3-acyl substituted tetrahydroquinolines 3,4-dihydroquinolin-2(1 )-ones from readily available feedstocks was developed by a hydride transfer strategy.

Language: Английский

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Visible-Light Mediated Metal-Free 6π-Photocyclization of N-Acrylamides: Thioxanthone Triplet Energy Transfer Enables the Synthesis of 3,4-Dihydroquinolin-2-ones

Organic Letters, Journal Year: 2021, Volume and Issue: 23(22), P. 8963 - 8967

Published: Nov. 10, 2021

An efficient thioxanthone-catalyzed triplet energy transfer process for the synthesis of 3,4-dihydroquinolin-2-ones via a 6π-photocyclization is reported. Featuring rare example metal-free formal C(sp2)-H/C(sp3)-H arylation mediated by visible-light, this work hopes to inspire further interest in these small molecules as sustainable alternatives existing transition-metal photocatalysts related processes.

Language: Английский

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Redox-triggered dearomative [5 + 1] annulation of indoles with O-alkyl ortho-oxybenzaldehydes for the synthesis of spirochromanes

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(6), P. 1668 - 1674

Published: Jan. 1, 2022

The dearomative [5 + 1] annulation of 2-methylindoles with new five-membered synthon was developed through cascade [1,5]-hydride transfer/dearomative cyclization in HFIP for the synthesis spirochromanes bearing 2-methylindolenine skeleton.

Language: Английский

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Alkyl amines and ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(4), P. 700 - 714

Published: Jan. 1, 2023

The use of alkyl amines and ethers as traceless hydride donors in [1,5]-hydride transfer cascade reactions has been reviewed herein.

Language: Английский

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Recent Advances for the Synthesis of Dihydroquinolin-2(1H)-ones via Catalytic Annulation of α,β-Unsaturated N-Arylamides

Catalysts, Journal Year: 2023, Volume and Issue: 13(7), P. 1105 - 1105

Published: July 15, 2023

Dihydroquinolin-2(1H)-ones (DHQOs) represent a class of valuable bioactive compounds with six-membered nitrogen-containing heterocyclic structures. The development simple, mild, and efficient synthetic methods has been widely considered by chemists. In this review, we have summarized series different strategies for the synthesis DHQOs via catalytic annulation α,β-unsaturated N-arylamides in past decade, including covering electrophilic cyclization, radical initiated photochemical cyclization reactions. Additionally, substrate scope mechanistic details are also discussed. This paper provides useful reference diverse methodologies DHQO.

Language: Английский

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Divergent application of 5-amino-isoxazoles for the construction of nitrogen heterocycles via the hydride transfer strategy

Organic Chemistry Frontiers, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The hydride transfer-enabled divergent application of 5-amino-isoxazoles for the controllable construction diverse tetrahydroquinolines and tetrahydroquinazolines was disclosed with employment different Lewis acids.

Language: Английский

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