Difluoromethylation of Unactivated Alkenes Using Freon-22 through Tertiary Amine-Borane-Triggered Halogen Atom Transfer

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(31), С. 14288 - 14296

Опубликована: Июль 27, 2022

The application of abundant and inexpensive fluorine feedstock sources to synthesize fluorinated compounds is an appealing yet underexplored strategy. Here, we report a photocatalytic radical hydrodifluoromethylation unactivated alkenes with industrial chemical, chlorodifluoromethane (ClCF2H, Freon-22). This protocol realized by merging tertiary amine-ligated boryl radical-induced halogen atom transfer (XAT) organophotoredox catalysis under blue light irradiation. A broad scope readily accessible featuring variety functional groups drug natural product moieties could be selectively difluoromethylated good efficiency in metal-free manner. Combined experimental computational studies suggest that the key XAT process ClCF2H both thermodynamically kinetically favored over hydrogen pathway owing formation strong boron–chlorine (B–Cl) bond low-lying antibonding orbital carbon–chlorine (C–Cl) bond.

Язык: Английский

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Highly Regio‐ and Enantioselective Hydrosilylation of gem‐Difluoroalkenes by Nickel Catalysis

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(10)

Опубликована: Дек. 27, 2021

The synthesis of small organic molecules with a difluoromethylated stereocenter is particularly attractive in drug discovery. Herein, we have developed an efficient method for the direct generation stereocenters through Ni0 -catalyzed regio- and enantioselective hydrosilylation gem-difluoroalkenes. reaction also represents construction carbon(sp3 )-silicon bonds nickel catalysis, which provides atom- step-economical route high-value optically active α-difluoromethylsilanes. This protocol features readily available starting materials commercial chiral broad substrates spanning range functional groups high yield (up to 99 % yield) excellent enantioselectivity 96 ee). enantioenriched products undergo variety stereospecific transformations. Preliminary mechanistic studies were performed.

Язык: Английский

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Catalytic stereodivergent total synthesis of amathaspiramide D

Nature Synthesis, Год журнала: 2022, Номер 1(5), С. 393 - 400

Опубликована: Май 12, 2022

Язык: Английский

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Single-atom skeletal editing of 2H-indazoles enabled by difluorocarbene

Science China Chemistry, Год журнала: 2023, Номер 66(7), С. 1975 - 1981

Опубликована: Май 11, 2023

Язык: Английский

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Fluorinated Sulfinates as Source of Alkyl Radicals in the Photo‐Enantiocontrolled β‐Functionalization of Enals

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(9)

Опубликована: Янв. 4, 2022

The generation of sulfonyl radicals has long been known as a flexible strategy in wide range different sulfonylative transformations. Meanwhile their use alkylation processes somehow limited due to inherent difficulty evolving less-stable after sulfur dioxide extrusion. Herein we report convenient that involves gem-difluorinated sulfinates an "upgrading-mask", allowing these precursors decompose into corresponding alkyl radicals. electron-donor character the formation electron donor-acceptor (EDA) complex with transient iminium ions is displayed, achieving first example stereocontrolled light-driven insertion gem-difluoro derivatives unsaturated aldehydes. This methodology compatible flow conditions, maintaining identical levels enantiocontrol.

Язык: Английский

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Direct C(sp³)–H difluoromethylation via radical–radical cross-coupling by visible-light photoredox catalysis

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(8), С. 2141 - 2148

Опубликована: Янв. 1, 2022

The first approach of photoredox catalyzed radical–radical cross-coupling difluoromethylation C(sp 3 )−H bond was reported, featuring transition metal-free, good functional group tolerance, broad substrate scope and mild reaction conditions.

Язык: Английский

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Metal-free synthesis of gem-difluorinated heterocycles from enaminones and difluorocarbene precursors

Chemical Communications, Год журнала: 2022, Номер 58(21), С. 3477 - 3480

Опубликована: Янв. 1, 2022

A cascade strategy to synthesise gem-difluorinated 2H-furans from reactions of BrCF2CO2Et with enaminones has been described. The tolerate a wide variety functional groups under metal-free conditions. An active aminocyclopropane is proposed be key intermediate through the cyclopropanation difluorocarbene enaminones, which further triggers regioselective C-C bond cleavage in situ afford corresponding 2H-furans.

Язык: Английский

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Copper-Catalyzed Hydroamination of gem-Difluoroalkenes Access to Diversified α-Difluoromethyl Amines

Organic Letters, Год журнала: 2023, Номер 25(3), С. 533 - 537

Опубликована: Янв. 13, 2023

The difluoromethyl group (CF2H) is of great importance in medicinal chemistry. We report herein an efficient method for the synthesis diversified α-difluoromethyl amines through copper-catalyzed hydroamination gem-difluoroalkenes, where C-N bond formed via a α-CF2H transition-metal intermediate. This new reaction proceeds Cu-H insertion to gem-difluoroalkenes and gives valuable alkyl-CF2H-containing compounds, which overcome much more challenged β-F elimination from α-fluoroalkyl organocopper species. exhibits broad substrate scope with readily available starting materials commercial catalysis.

Язык: Английский

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Metal-free synthesis of difluoro/trifluoromethyl carbinol-containing chromones via tandem cyclization of o-hydroxyaryl enaminones

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(46), С. 9236 - 9241

Опубликована: Янв. 1, 2023

A convenient and efficient method for the synthesis of difluoro/trifluoromethyl carbinol-containing chromone derivatives has been developed.

Язык: Английский

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Diastereo- and Enantioselective Dearomative Reductive Aryl-Fluoroalkenylation of Indoles by Nickel Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(9), С. 6432 - 6439

Опубликована: Апрель 11, 2024

Herein, we disclose a nickel-catalyzed dearomative reductive aryl-fluoroalkenylation of indoles by defluorinative coupling with gem-difluoroalkenes. The catalytic protocol affords facile assembly various monofluoroalkene-containing polycyclic fused indolines bearing two contiguous carbon stereocenters in high diastereo- and enantioselectivities tolerance diverse functional groups.

Язык: Английский

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