Photouranium-Catalyzed C–F Activation Hydroxylation via Water Splitting

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: April 9, 2024

The C–F bond is the strongest covalent single (126 kcal/mol) in carbon-centered bonds, which highest electronegativity of fluorine (χ = 4) gives rise to shortest length (1.38 Å) and smallest van der Waals radius (rw 1.47 Å), resulting enormous challenges for activation transformation. Herein, conversion was realized via photouranium-catalyzed hydroxylation unactivated aryl fluorides using water as a hydroxyl source deliver multifunctional phenols under ambient conditions. featured cascade sequences electron transfer (SET)/hydrogen atom (HAT)/oxygen (OAT), highly integrated from excited uranyl cation. *UO22+ prompted splitting mild photoexcitation, caging active oxygen peroxo-bridged manner critical OAT process releasing hydrogen HAT process.

Language: Английский

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Electrosynthetic C–F bond cleavage

Organic & Biomolecular Chemistry, Journal Year: 2022, Volume and Issue: 20(34), P. 6707 - 6720

Published: Jan. 1, 2022

Fluorinated organic compounds are common among pharmaceuticals, agrochemicals and materials. The significant strength of the C-F bond results in chemical inertness that, depending on context, is beneficial, problematic or simply a formidable synthetic challenge. Electrosynthesis rapidly expanding methodology that can enable new reactivity selectivity for cleavage formation bonds. Here, comprehensive overview synthetically relevant electrochemically driven protocols activation functionalization presented, including photoelectrochemical strategies.

Language: Английский

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Nickel-catalysed chelation-assisted reductive defluorinative sulfenylation of trifluoropropionic acid derivatives

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(17), P. 2405 - 2408

Published: Jan. 1, 2024

Nickel-catalysed chelation-assisted reductive cross-coupling of trifluoropropanamides/esters with disulfides to afford thioacrylamides/esters high E selectivity, involving triple C–F bond cleavage.

Language: Английский

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Cryogenic Organometallic Carbon–Fluoride Bond Functionalization with Broad Functional Group Tolerance

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 6, 2025

The unique properties of fluorinated organic compounds have received intense interest and conquered a myriad applications in the chemical pharmaceutical sciences. Today, an impressive range alkyl fluorides are commercially available, there many practical methods to make them exist. However, unmatched stability inertness C–F bond largely limited its synthetic value, which is very different from widely accepted utility chlorides, bromides, iodides that serve everyday as "workhorse" building blocks countless carbon–carbon forming reactions. This study demonstrates high-yielding functionalization under mild conditions, i.e., at temperatures low −78 °C, short reaction times with unconventional chemoselectivity. Cryogenic Csp3–F cleavage using fluorophilic organoaluminum together fast nucleophile transfer intermediate ate complexes forge bonds unactivated primary, secondary, tertiary alike. method, exploits Al–F thermodynamic driving force, highly selective toward functionalization, whereas other functional groups including chloride, bromide, iodide, aryl halide, alkenyl, alkynyl, difluoroalkyl, trifluoromethyl, ether, ester, hydroxyl, acetal, heteroaryl, nitrile, nitro, amide tolerated, unexpected reversal long-standing main group organometallic halide cross-coupling reactivity compatibility patterns. As result, strongest single chemistry can now be selectively targeted arylation, alkylation, alkenylation, alkynylation reactions used late-stage complementary currently available methods.

Language: Английский

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General alkyl fluoride functionalization via short-lived carbocation-organozincate ion pairs

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Feb. 29, 2024

Abstract Fluorinated organic compounds are frequently used across the chemical and life sciences. Although a large, structurally diverse pool of alkyl fluorides is nowadays available, synthetic applications trail behind widely accepted utility other halides. We envisioned that C(sp 2 )-C(sp 3 ) cross-coupling reactions with fluorophilic organozinc should be possible through heterolytic mechanism involves short-lived ion pairs uses stability Zn-F bond as thermodynamic driving force. This would mechanistically different from previously reported radical overcome long-standing limitations organometallic methodology, including competing β-hydride elimination, homodimerization hydrodefluorination. Here, we show practical C sp3 -F functionalization method expands currently restricted space unactivated primary, secondary tertiary )-F bonds but also benzylic, propargylic acyl fluorides. Many functional groups sterically demanding substrates tolerated, which allows carbon-carbon formation late-stage functionalization.

Language: Английский

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Organocuprate Cross–Coupling Reactions with Alkyl Fluorides

Organic Letters, Journal Year: 2022, Volume and Issue: 24(47), P. 8719 - 8723

Published: Nov. 17, 2022

Cross-coupling of alkyl fluorides and organocuprates is accomplished via aluminum halide mediated C-F bond activation subsequent Csp2-Csp3 Csp3-Csp3 formation. Relatively mild conditions allow for smooth notoriously challenging primary secondary while competing chain rearrangement, HF elimination, homocoupling reactions are effectively controlled. The utility functional group tolerance demonstrated with 23 examples a variety coupling products obtained in up to 88% yield.

Language: Английский

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Cross‐ and Multi‐Coupling Reactions Using Monofluoroalkanes

The Chemical Record, Journal Year: 2023, Volume and Issue: 23(9)

Published: April 18, 2023

Abstract Carbon‐fluorine bonds are stable and have demonstrated sluggishness against various chemical manipulations. However, selective transformations of C−F can be achieved by developing appropriate conditions as useful synthetic methods in organic chemistry. This review focuses on C−C bond formation at monofluorinated sp 3 ‐hybridized carbons via cleavage, including cross‐coupling multi‐component coupling reactions. The cleavage mechanisms the carbon centers primarily categorized into three types: Lewis acids promoted F atom elimination to generate carbocation intermediates; nucleophilic substitution with metal or nucleophiles supported activation coordination acids; a single electron transfer. characteristic features alkyl fluorides, comparison other (pseudo)halides promising electrophilic counterparts, also discussed.

Language: Английский

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Copper Catalyzed Defluoroarylation of gem-Difluoroallenes to Allenyl Monofluorides with Aryl Boronic Esters

Organic Letters, Journal Year: 2023, Volume and Issue: 25(24), P. 4546 - 4550

Published: June 8, 2023

Few studies have been performed on allenyl monofluorides, especially aryl-substituted frames, due to concerns about their stability. Here we report a copper-catalyzed regioselective synthesis of such structures with inexpensive and accessible aryl boronic esters under mild conditions. Arylated monofluorides were stable enough be isolated easily converted various other fluorine-containing blueprints. Preliminary asymmetric attempts demonstrate that the reaction could proceed via selective β-fluorine elimination process.

Language: Английский

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Enantioselective Lewis Base Catalysed Allylation of Picoline- and Quinaldine-based Latent Pronucleophiles

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(33), P. 6684 - 6689

Published: Jan. 1, 2024

The concept of latent pronucleophiles enables selective allylation picolines and quinaldines with allylic fluorides in the presence Lewis base catalysts. products are isolated as single regioisomers good yields enantioselectivity.

Language: Английский

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A silylboronate-mediated strategy for cross-coupling of alkyl fluorides with aryl alkanes: mechanistic insights and scope expansion

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The construction of C(sp

Language: Английский

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