Synthetic Advantages of Defluorinative C−F Bond Functionalization

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(49)

Опубликована: Авг. 22, 2023

Abstract Much progress has been made in the development of methods to both create compounds that contain C−F bonds and functionalize bonds. As such, are becoming common versatile synthetic functional handles. This review summarizes advantages defluorinative functionalization reactions for small molecule synthesis. The coverage is organized by type carbon framework fluorine attached mono‐ polyfluorinated motifs. main challenges, opportunities advances discussed each class organofluorine. Most text focuses on case studies illustrate how defluorofunctionalization can improve routes targets or properties enable unique mechanisms reactions. broader goal showcase incorporating exploiting design routes, improvement specific advent new methods.

Язык: Английский

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Bi-Catalyzed Trifluoromethylation of C(sp²)–H Bonds under Light

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(47), С. 25538 - 25544

Опубликована: Ноя. 14, 2023

We disclose a Bi-catalyzed C–H trifluoromethylation of (hetero)arenes using CF3SO2Cl under light irradiation. The catalytic method permits the direct functionalization various heterocycles bearing distinct functional groups. structural and computational studies suggest that process occurs through an open-shell redox manifold at bismuth, comprising three unusual elementary steps for main group element. cycle starts with rapid oxidative addition to low-valent Bi(I) catalyst, followed by light-induced homolysis Bi(III)–O bond generate trifluoromethyl radical upon extrusion SO2, is closed hydrogen-atom transfer Bi(II) intermediate.

Язык: Английский

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Nickel-Catalyzed Enantioconvergent and Diastereoselective Allenylation of Alkyl Electrophiles: Simultaneous Control of Central and Axial Chirality

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(11), С. 7173 - 7177

Опубликована: Март 6, 2024

In recent years, remarkable progress has been described in the development of methods that simultaneously control vicinal stereochemistry, wherein both stereochemical elements are central chirality; contrast, and axial chirality comparatively rare. Herein we report a chiral nickel catalyst achieves enantioconvergent diastereoselective coupling racemic secondary alkyl electrophiles with prochiral 1,3-enynes (in presence hydrosilane) to generate tetrasubstituted allenes bear an adjacent stereogenic center. A carbon–carbon carbon–hydrogen bond formed this process, which provides good stereoselectivity is compatible array functional groups.

Язык: Английский

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9-(4-Halo-2,6-xylyl)-10-methylacridinium Ion as an Effective Photoredox Catalyst for Oxygenation and Trifluoromethylation of Toluene Derivatives

ACS Catalysis, Год журнала: 2024, Номер 14(4), С. 2671 - 2684

Опубликована: Фев. 6, 2024

9-(2,6-Dimethylphenyl)-10-methylacridinium perchlorate ([Acr+–Xyl]ClO4–), 9-(4-chloro-2,6-dimethylphenyl)-10-methylacridinium ([Acr+–XylCl]ClO4–), and 9-(4-fluoro-2,6-dimethylphenyl)-10-methylacridinium ([Acr+–XylF]ClO4–) were synthesized by the Grignard reaction. The one-electron reduction potentials (Ered vs SCE) of Acr+–Xyl, Acr+–XylCl, Acr+–XylF in deaerated acetonitrile (MeCN) determined cyclic voltammetry to be nearly same as −0.55, −0.53, −0.53 V, respectively. On other hand, oxidation (Eox Acr+–XylF, Acr+–XylCl second-harmonic alternative current voltammetric method +2.15, +2.20, +2.21 Eox value is higher than toluene (+2.20 V). Thus, photocatalytic oxygenation with oxygen occurs efficiently via electron transfer from XylCl•+ moiety triplet electron-transfer state under photoirradiation oxygen-saturated MeCN. By contrast, no occurred 9-mesityl-10-methylacridinium ion (Acr+–Mes) used a photocatalyst due lack oxidizing ability oxidize toluene. metal-free trifluoromethylation derivatives has also been made possible using S-(trifluoromethyl)dibenzothiophenium (CF3DBT+) trifluoromethyl source. reaction mechanism was clarified transient absorption electrochemical measurements.

Язык: Английский

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Construction of trifluoromethyl-containing heterocycles from trifluoroacetimidoyl chlorides and derivatives

Chemical Communications, Год журнала: 2023, Номер 59(33), С. 4872 - 4890

Опубликована: Янв. 1, 2023

Recent advances in the direct synthesis of trifluoromethyl-containing heterocycles from trifluoroacetimidoyl chlorides (TFAICs) and derivatives, including trifluoroacetimidohydrazides (TFAIHs) CF3-imidoyl sulfoxonium ylides (TFISYs), are systematically summarized discussed. The cascade annulation reactions synthons with suitable coupling partners have emerged as a powerful promising tool for construction variety trifluoromethyl-substituted heterocycles. Compared other building blocks, TFAICs derivatives notable merits easy availability handling, relative stability safety, high reactivity.

Язык: Английский

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Selectively Tunable Synthesis of α-Trifluoromethyl Ketones

Organic Letters, Год журнала: 2023, Номер 25(13), С. 2344 - 2348

Опубликована: Март 23, 2023

A cross-coupling of aldehydes and α-trifluoromethyl alkyl bromides was developed via dual nickel/photoredox catalysis system. wide variety substrates bearing a diverse set functional groups were compatible to afford ketones under very mild conditions (visible light, ambient temperature, no strong base). Selectively tunable access these with the trifluoromethyl group on any one side can be smoothly obtained by simply modulating different reagents. Meanwhile, asymmetric pattern also investigated.

Язык: Английский

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Synthesis of Trifluoromethyl-Substituted Allenols via Catalytic Trifluoromethylbenzoxylation of 1,3-Enynes

ACS Catalysis, Год журнала: 2023, Номер 13(3), С. 2142 - 2148

Опубликована: Янв. 25, 2023

Allenol has been identified as a versatile building block for organic synthesis, and numerous efforts have made to synthesize apply allenol. However, limited obtain trifluoromethyl-substituted Here, by using readily available 1,3-enyne the starting material, copper-catalyzed trifluoromethylbenzoxylation process was developed efficient synthesis of allenols Togni-II reagent reaction partner. Triple roles reagent, including source trifluoromethyl group, hydroxyl oxidant, were elucidated in this transformation. Moreover, late-stage diversification performed, which revealed application potential preparation various compounds.

Язык: Английский

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Synthesis of Alkynylsilanes: A Review of the State of the Art

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер 366(11), С. 2382 - 2431

Опубликована: Апрель 12, 2024

Abstract This contribution offers a comprehensive overview of methods for forging sp C−Si bonds. Over time, alkynylsilanes (silylacetylenes), once considered mere byproducts hydrosilylation processes, have become essential building blocks in organic synthesis. literature review traces the evolution their synthesis, from traditional methodologies relying on organolithium and organomagnesium compounds to more advanced cross‐coupling reactions involving hydro‐ carbosilanes. Focused primarily past 25 years (2000–2024), it also extensively references significant historical breakthroughs. By analyzing synthetic methodologies, not only survey current state knowledge but identifies areas improvement. Furthermore, emphasize importance 1‐alkynylsilanes (1‐silyl‐1‐alkynes), selected applications these are highlighted, confirming potential

Язык: Английский

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EDA Complex-Enabled Annulation to Access CF₂-Containing Tetralones and Quinazolinones Using Persulfates as Electron Donors

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 10614 - 10623

Опубликована: Июль 25, 2024

A photocatalyst-free and EDA complex-enabled radical cascade cyclization reaction of inactive alkenes with bromodifluoroacetamides was reported for the divergent synthesis fluorine-containing tetralones quinazolinones. In this transformation, persulfates as electron donors difluoro bromamide acceptors generate complex. This is a promising photochemical method advantages such mild conditions, simple operation, being metal-free, excellent functional group tolerance.

Язык: Английский

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Recent advances in the application of Langlois’ reagent in olefin difunctionalization

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 21(10), С. 2046 - 2058

Опубликована: Ноя. 18, 2022

This review describes several key activation methods for Langlois' reagent in the difunctionalization of alkenes and could stimulate interest readers promoting wider development application reagent.

Язык: Английский

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