Construction of C−S and C−Se Bonds from Unstrained Ketone Precursors under Photoredox Catalysis

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(8)

Published: Jan. 5, 2024

Abstract A mild photoredox catalyzed construction of sulfides, disulfides, selenides, sulfoxides and sulfones from unstrained ketone precursors is introduced. Combination this deacylative process with S N 2 or coupling reactions provides novel convenient modular strategies toward unsymmetrical symmetric disulfides. Reactivity studies favor a bromine radical that initiates HAT (Hydrogen Atom Transfer) the aminal intermediate resulting in expulsion C‐centered intercepted to make C−S C−Se bonds. Gram scale reactions, broad substrate scope tolerance towards various functional groups render method appealing for future applications synthesis organosulfur selenium complexes.

Language: Английский

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Visible-Light-Induced Cascade Radical Cyclization to Access Sulfamoylated Benzo[4,5]imidazo[2,1-a]isoquinolin-6(5H)-ones

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 3, 2024

A visible-light-induced cascade radical sulfamoylation/cyclization of 2-arylbenzoimidazoles to access sulfamoylated benzo[4,5]imidazo[2,1- a ]isoquinolin-6(5 H )-ones was achieved.

Language: Английский

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Pro‐aromatic Dihydroquinazolinones – From Multigram Synthesis to Reagents for Gram‐scale Metallaphotoredox Reactions

Chemistry - An Asian Journal, Journal Year: 2023, Volume and Issue: 19(3)

Published: Dec. 16, 2023

Abstract Dihydroquinazolinone (DHQZ) has recently been harnessed as a ketone‐derived pro‐aromatic reagent extensively employed in (metalla)photoredox reactions versatile group transfer agents. In this work, we outline column chromatography‐free protocol for the multigram‐scale synthesis of DHQZs well its use gram‐scale nickel/photoredox dual‐catalyzed cross‐coupling single‐batch, photoflow, and simultaneous multiple smaller batches. While single‐batch approach leveraged moderate yields, simple plug‐flow photoreactor also exhibited amenable productivity (up to 45 % yield) despite heterogeneous base. Meanwhile, performing metallaphotoredox‐catalyzed reaction batches an improvised facilitated high yields up 59 good reproducibility, implying convenient alternative absence photoflow setups.

Language: Английский

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Direct excitation strategy for deacylative couplings of ketones

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(42)

Published: July 24, 2024

Abstract The homolysis of chemical bonds represents one the most fundamental reactivities excited molecules. Historically, it has been exploited to generate radicals under ultraviolet (UV) light irradiation. However, unlike contemporary radical‐generating mechanisms, direct excitation homolyze and produce aliphatic carbon‐centered visible remains rare, especially in metallaphotoredox cross couplings. Herein, we present our design dihydropyrimidoquinolinone (DHPQ) reagents derived from ketones, which can undergo formal deacylation homolytic C−C bond cleavage release alkyl without external photocatalysts. Spectroscopic computational analysis reveal unique optical structural features DHPQs, rationalizing their faster kinetics radical generation than a structurally similar but visible‐light transparent precursor. Such capability allows DHPQ facilitate wide range Ni‐metallaphotoredox couplings with aryl, alkynyl acyl halides. Other catalytic non‐catalyzed alkylative transformations DHPQs are also feasible various acceptors. We believe this work would be broad interest, aiding synthetic planning simplified operation expanding reach photocatalyst‐free approaches cutting‐edge research.

Language: Английский

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Transition-metal-free tandem cyclization by radical NHC catalysis: Rapid access to indolo[2,1‑a]isoquinolines

Tetrahedron Letters, Journal Year: 2024, Volume and Issue: unknown, P. 155319 - 155319

Published: Oct. 1, 2024

Language: Английский

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Electrochemical C H alkylation of N-heterocycles via aromatization-driven C C fragmentation of unstrained ketones

Tetrahedron Letters, Journal Year: 2024, Volume and Issue: 155, P. 155440 - 155440

Published: Dec. 27, 2024

Language: Английский

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