Concomitant (3 + 3) Annulation/Fragmentation of Triazinanes with Enamines: Electrosynthesis of Multisubstituted Dihydropyrimidines

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

Published: March 6, 2025

An electro-oxidative formal (3 + 3) annulation of 1,3,5-triazinanes with enamines toward multisubstituted 1,2-dihydropyrimidines is reported. This metal-free mild protocol offers wide functional group tolerance, and heterocycles an unexplored molecular scaffold were constructed in excellent yields. Mechanistically, the electro-oxidation triazinane nucleophilic reactivity enamine result a concomitant annulation-fragmentation process, leading to six-membered heterocyclic product.

Language: Английский

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Photoredox Radical Cyclization of o-Vinylaryl Isocyanides and Aryldiazonium Tetrafluoroborates for the Synthesis of 2,4-Disubstituted Quinolines

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: March 23, 2025

Quinolines, a significant part of nitrogen-containing heterocycles, are widely found in functional compounds. Herin, photochemical radical cyclization reaction o-vinylaryl isocyanides and aryldiazonium tetrafluoroborates, has been reported to build 2,4-diaryl quinolines. Readily accessible aryl diazonium salts were utilized as precursors at room temperature. This approach allowed good group tolerance substrate applicability.

Language: Английский

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Metal-Free Visible-Light Excitation of TMSN₃ Enables [3 + 2] Cycloaddition of Arylidenecyclopropanes with Olefins

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

Published: April 14, 2025

A visible-light photoredox [3 + 2] cycloaddition reaction of arylidenecyclopropanes with olefins was developed, employing the readily available and commercially accessible TMSN3 as an efficient radical mediator. This method provides a convenient route to arylidenecyclopentanes from starting materials, is metal-free, features enhanced atom step economy, excellent selectivity, extensive substrate versatility, favorable functional group compatibility, structural diversity, mild conditions, which further enable late-stage diversification. DFT calculations elucidated that this transformation entails sequential generation, addition, ring-opening, cyclization, elimination steps.

Language: Английский

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Fe-Catalyzed Radical Trifluoromethylation and Cyclization of Ortho-Vinyl Enaminones with 1-(Trifluoromethyl)-1,3-benzo-[d][1,2]iodaoxol-3(1H)-one to Construct Functionalized Quinolines

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: May 19, 2025

Herein, we present a protocol for the construction of functionalized quinolines, i.e., 3-acyl-4-(2,2,2-trifluoro-ethyl)quinolines (ATFQLs) 4, from ortho-vinyl enaminones and 1-(trifluoromethyl)-1,3-benzo-[d][1,2]-iodaoxol-3(1H)-one, which was catalyzed by FeCp2 promoted FeCl3 (Lewis acid) additives in solvents (i.e., acetonitrile toluene). This strategy first utilized FeCp2-catalyzed functionalization alkenes with trifluoromethyl radicals. The intermediate formed captured ortho-iodobenzoate substrate, yielding 3, then underwent FeCl3-catalyzed elimination at higher temperature to form an α,β-unsaturated intermediate. subsequent intramolecular Michael reaction yielded final target compound 4. In summary, series ATFQLs 4 were synthesized through formation two bonds (C═C C-C).

Language: Английский

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Dual Functionalization of the α,β-C–H Bonds in Alanine Ester Derivatives via Enamine–Imine Tautomerism: Construction of 4-Quinolinolate Skeletons through a Fragmentation–Reassembly Pathway

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 16, 2024

Using a SbCl

Language: Английский

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