Dearomative 1,4-Difunctionalization of Non-Activated Arenes Enabled by Boryl Radical-Mediated Halogen-Atom Transfer

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 1294 - 1304

Published: Jan. 7, 2025

Given the widespread presence of spirocyclic scaffolds in natural products and pharmacologically relevant synthetic compounds, development efficient methodologies for their construction holds great importance medicinal chemistry pharmaceutical research. In this study, a general photochemical dearomative spirocyclization nonactivated arenes has been established. The key to method lies ability amine-borane radicals activate aryl bromides iodides via halogen-atom transfer, thereby allowing conversion halides into corresponding subsequent chemodivergent transformations. remarkable compatibility versatility 1,4-difunctionalization is showed by rapid assembly structurally diverse 1,4-cyclohexadiene-based spirocycles incorporating oxindole, indoline, or dihydrobenzofuran subunits. Moreover, potential utility protocol exemplified formal total synthesis vasopressin V2 receptor antagonist Satavaptan.

Language: Английский

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Photocatalytic [3 + 2]-annulation via sodium tetraarylborate: a fundamental approach for synthesizing 1,4,2-diazaborole analogs

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Nitriles stabilize neutral diarylboryl radicals, generating the RCN-BAr 2 complex, an efficient boron-nitrogen synthon that reacts with imines and olefins for photocatalytic synthesis of boron–nitrogen heterocycles, such as 1,4,2-diazaboroles.

Language: Английский

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CO₂^•– Enabled Synthesis of Phenanthridinones, Oxindoles, Isoindolinones, and Spirolactams

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

Published: Feb. 28, 2025

We report herein that photoinduced CO2•– enabled reductive intramolecular radical cyclization of a variety aryl iodide derivatives to the corresponding phenanthridinone, oxindole, isoindolinone, and spirolactam in good yields. Preliminary mechanistic studies suggested generation through homolysis cesium formate presence light, further involvement was directly proved by trapping with diphenyl styrene TEMPO.

Language: Английский

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Controllable Hydrodebromination of Tribromomethyl Groups via Lewis Base–Borane-Mediated Ionic and Radical Pathways

Synthesis, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 2, 2025

Abstract Compounds bearing mono- and dibromomethyl groups are extensively utilized in synthetic medicinal chemistry. In this regard, selective debromination of readily or easily accessible tribromomethyl compounds offers a direct efficient method to access those two moieties. work, we introduced Lewis base–borane-mediated hydrodebromination via ionic radical pathway. Using 4-(dimethylamino)pyridine–borane (DMAP-BH3) as hydride donor, monohydrodebromination was achieved nucleophilic substitution by hydride, delivering groups. On the other hand, treatment with an N-heterocyclic carbene–borane (NHC-BH2CN) boryl precursor presence dilauroyl peroxide (DLP) initiator afforded monobromomethyl through consecutive bromine atom abstractions cleave C–Br bonds. Various group acetamides acetates were applied developed protocol, showcasing good functional tolerance broad substrate scope.

Language: Английский

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Translation of Nickel-Catalyzed C(sp²)–C(sp³) Cross-Electrophile Coupling to Non-Amide Solvents

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

Published: April 14, 2025

The cross-electrophile coupling of organobromides is widely utilized in organic synthesis but generally requires undesirable amide solvents (e.g., DMF, DMA, and NMP). We report that the combination a strongly donating, bidentate nitrogen ligand, LiI, 4-picoline enables variety alcohol, ester, ethereal at up to 50 g scale. An improved optimal 4,4'-bis(dimethylamino)-2,2'-bipyridine, also reported on basis reductive homocoupling 4-dimethylamino-2-chloropyridine.

Language: Английский

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Nickel/Photoredox Dual-Catalyzed, Regioselective 1,2-Carboacylation of Alkenes via Synergistic Alkyl and Benzoyl Radical Coupling

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

Published: May 2, 2025

A regioselective 1,2-carboacylation protocol of alkenes via nickel/photoredox dual catalysis has been successfully developed under mild conditions. wide range alkyl bromides, α-oxocarboxylic acids, and styrenes proved to be compatible the optimized conditions, affording corresponding products in up 91% yields. Mechanistically, key success this approach is temporal orchestration radical generation: nickel-catalyzed halogen atom transfer (XAT) for bromides photoredox-driven decarboxylation acids.

Language: Английский

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Photoredox Nickel-Catalyzed Radical Cyclization of N-Arylacrylamides with Alkyl Bromides

Organic & Biomolecular Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

We present a photoredox nickel-catalyzed intermolecular cyclization between N -arylacrylamides and readily accessible alkyl bromides, which affords diverse range of 3,3-disubstituted oxindoles in moderate to high yields.

Language: Английский

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MeOH-Triggered Halogen-Atom Transfer of Unactivated Alkyl Bromides Enabling the Photoredox Giese Addition

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

Published: March 18, 2025

Herein, a nickel-catalyzed, photoredox Giese addition reaction with readily accessible alkyl bromides, driven by available feedstock MeOH as the halogen-atom transfer (XAT) reagent, was successfully achieved under mild conditions. The versatility of this protocol demonstrated through range structurally varied bromides and Giese-type acceptors moderate to good yields. Mechanistic investigation highlights that formation radicals XAT tentatively prompted •CH2OH, which derived from sequential photo-oxidation/1,2-hydrogen-atom MeOH.

Language: Английский

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