Regioselective C₃Alkylation of Indoles for the Synthesis of Bis(indolyl)methanes and 3-Styryl Indoles

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(3), P. 1846 - 1857

Published: Jan. 12, 2024

Herein, we describe an efficient transition-metal-free regioselective C3alkylation of indoles for the synthesis bis(indolyl)methanes and 3-styryl indoles. Nitrobenzene is employed as oxidant to oxidize alcohols in presence a strong base reaction avoids use transition metals such Ru Mn. The protocol provides favorable route access biologically active compounds arundine, vibrindole A, turbomycin B.

Language: Английский

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Visible Light-Driven α-Diazoketones as Denitrogenated Synthons: Synthesis of Fluorinated N-Heterocycles via Multicomponent Cyclization Reactions

Organic Letters, Journal Year: 2023, Volume and Issue: 25(18), P. 3314 - 3318

Published: May 1, 2023

We disclose herein an efficient photochemical formal [3+2+1] annulation strategy for the transformation of diazocarbonyl compounds into various fluorinated nitrogen-containing heterocycles. This is characterized by reacting fluoroalkyl radicals with α-diazoketones, which are used as infrequent denitrogenated synthons under visible light. Moreover, a wide range N-heterocycles containing precious CF3 and perfluoroalkylated groups constructed in moderate to good yields. Notably, this may provide fruitful path synthesis complex organofluorides via diazo/fluorine/radical chemistry.

Language: Английский

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Chloride‐Promoted Photoelectrochemical C—H Silylation of Heteroarenes^†

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 41(22), P. 2963 - 2968

Published: June 24, 2023

Comprehensive Summary A photoelectrochemical approach for the C—H silylation of heteroarenes through dehydrogenation cross‐coupling with H 2 evolution has been developed. The depends on hydrogen atom transfer (HAT) from silanes to Cl‐radical generated light‐induced homolytic cleavage Cl , in which was produced by electrochemical oxidation chloride. large number silylated heterocyclic molecules are rapidly constructed satisfactory yields without relying oxidants and metal reagents.

Language: Английский

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Copper-catalyzed divergent construction of naphthofurans and benzochromanes from 2-naphthols, 4-methylene-quinazolin(thi)ones, and N,N-dimethylethanolamine

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(4), P. 1198 - 1204

Published: Jan. 1, 2024

Cu( ii )-catalyzed divergent synthesis of naphthofurans and benzochromanes through [3 + 2 1] 1 annulations is established.

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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Asymmetric Dearomatization of Nonfunctionalized 1-Naphthols via Copper-Catalyzed Enantioselective [4 + 1] Spiroannulation

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(12), P. 9244 - 9253

Published: June 3, 2024

Catalytic asymmetric dearomatization (CADA) is a powerful tool for the rapid construction of complex chiral three-dimensional cyclic molecules featuring quaternary carbon centers from readily available arenes. However, ubiquitous nonfunctionalized 1-naphthols to afford remains challenging and undeveloped. This study reports dearomative [4 + 1] spiroannulation via copper catalysis. reaction features highly chemo-, regio-, stereoselective nucleophilic addition intramolecular annulation cascade reactive π-extended copper-allenylidene, thus enabling practical synthesis range valuable spirocyclic enones bearing stereocenter with high efficiency. Furthermore, this protocol applicable phenols. Control experiments supported substitution-annulation mechanism by excluding process involving 1,3-sigmatropic shift. Preliminary biological activity studies indicated that synthesized hold significant promise as anticancer agents inducing tumor cell apoptosis.

Language: Английский

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Metal-free construction of dihydropyrazino[2,3-b]indoles from 2-aminoacetophenones, isocyanates and 1,2-diamines

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(10), P. 2043 - 2048

Published: Jan. 1, 2024

A Brønsted acid/iodine co-mediated approach to construct dihydropyrazino[2,3-

Language: Английский

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Synthesis of homophthalimide spironaphthalenones through [5 + 1] spiroannulation of aryl/alkenyl enaminones with diazo homophthalimides

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(17), P. 4282 - 4288

Published: Jan. 1, 2023

Presented herein is a novel synthesis of homophthalimide spironaphthalenones from the cascade reaction enaminones with diazo homophthalimides.

Language: Английский

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Substrate‐induced Selective α‐C(sp³)−H Activation of N‐alkyl Amines: Synthesis of Coumarin‐fused Quinolinones under Air

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(6), P. 1430 - 1435

Published: Jan. 23, 2024

Abstract A substrate‐induced synthesis of coumarin‐fused quinolinones is achieved from 4‐(phenylamino)‐2 H ‐chromen‐2‐ones using N ‐alkyl amines as the solvent and a carbon source under air conditions without any catalysts in one pot. This protocol highlights special roles which were not only used reactants but also an internal oxidant selectively activated ‐ α ‐C( sp 3 )−H bond. reaction features catalyst‐free, broad substrate scopes ( 27 examples 24 examples), operationally simple for one‐step synthesis, recovery recycling solvent.

Language: Английский

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Cu-Catalyzed Carbocyclization for General Synthesis of N-Containing Heterocyclics Enabled by BrCF₂COOEt as a C1 Source

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(5), P. 3403 - 3412

Published: Feb. 8, 2024

A practical and efficient copper-catalyzed carbocyclization of 2-functionalized anilines with ethyl bromodifluoroacetate has been developed. Ethyl is employed as the C1 source via quadruple cleavage in this transformation. This reaction can afford a variety N-containing heterocyclics satisfactory yields excellent functional group compatibility.

Language: Английский

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