A Base-Promoted Reductive Coupling Platform for the Divergent Defluorofunctionalization of Trifluoromethylarenes

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(29), С. 13032 - 13038

Опубликована: Июль 14, 2022

We report a trifluoromethylarene reductive coupling method that dramatically expands the scope of difluorobenzylic substructures accessible

Язык: Английский

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Modularity in the C_sp3 Space─Alkyl Germanes as Orthogonal Molecular Handles for Chemoselective Diversification

ACS Catalysis, Год журнала: 2022, Номер 12(9), С. 4833 - 4839

Опубликована: Апрель 8, 2022

To meet the need for a rapid, streamlined, and potentially automatable molecule synthesis, modular coupling approaches are highly desired. While diversification of aromatic molecules, i.e., Csp2 space, has greatly advanced, syntheses in Csp3 space comparably much less developed. This report explores potential alternative functional handles, alkyl germanes, this context, which combine features stability synthesizability with selective reactivity. We show chemoselective functionalization germanes (R-GeEt3) under photoredox conditions (Giese addition) implementation building block, allows Csp3-halogen vs Csp3-Bpin Csp3-GeEt3 sites.

Язык: Английский

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Reverse Regioselective Cp*Co(III)-Catalyzed [4 + 2] C–H Annulation of N-Chloroamides with Vinylsilanes: Synthesis of 4-Silylated Isoquinolones and Their Synthetic Utilities

Organic Letters, Год журнала: 2023, Номер 25(43), С. 7878 - 7883

Опубликована: Окт. 23, 2023

We have developed a Cp*Co(III)-catalyzed reverse regioselective [4 + 2] annulation of N-chlorobenzamides/acrylamides with vinylsilanes for the synthesis 4-silylated isoquinolones. The reaction was performed at ambient temperature under redox-neutral conditions. utilized N-Cl bond as an internal oxidant, furnished required products excellent regioselectivities, and demonstrated high functional group tolerance. synthetic utility isoquinolones has been preparation 4-heteroarylated 4-alkylated via metal-free C-C couplings. Additionally, 3,4-dihydroisoquinolones were synthesized protodesilylation isoquinolones, thus making vinylsilane ethylene surrogate.

Язык: Английский

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Axially Chiral Bridged Biaryls by Ni-Catalyzed Kinetic Asymmetric C–O Bond Cleavage

ACS Catalysis, Год журнала: 2024, Номер 14(11), С. 8176 - 8183

Опубликована: Май 10, 2024

Axially chiral bridged biaryls represent an important subset of axially biaryl scaffolds in fields ranging from organic synthesis to biochemistry materials science. While numerous catalytic strategies have been elucidated for the construction axial chirality, enantioenriched form remains underdeveloped. Herein, we demonstrate approach synthesize diverse through nickel-catalyzed kinetic asymmetric cleavage unactivated aromatic C–O bond. The system features mild reaction conditions, high resolution efficiency, and versatile post-functionalizations. Mechanistic studies reveal impact nickel catalyst's chirality on stereochemical output this transformation.

Язык: Английский

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Electrochemistry-Enabled C-Heteroatom Bond Formation of Alkyl Germanes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(31), С. 21257 - 21263

Опубликована: Июль 26, 2024

Because of their robustness and orthogonal reactivity features, alkyl germanes bear significant potential as functional handles for the construction C(sp3)-rich scaffolds, especially in context modular synthetic approaches. However, to date, only radical-based has been accessible from these handles, which limits types possible decorations. Here, we describe first general C(sp3)–heteroatom bond formation (−GeEt3) by leveraging electrochemistry unlock polar reactivity. This approach allowed us couple C(sp3)–GeEt3 with a variety nucleophiles construct ethers, esters, amines, amides, sulfonamides, sulfides, well C–P, C–F, C–C bonds. The compatibility electrochemical strategy C1 motif was also showcased, involving sequential functionalization Cl, Bpin, ultimately GeEt3 via electrochemistry.

Язык: Английский

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Palladium‐Catalyzed Aryldifluoromethylation of Aryl Halides with Aryldifluoromethyl Trimethylsilanes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(41)

Опубликована: Авг. 12, 2022

Abstract Diaryl difluoromethanes are valuable targets for medicinal chemistry because they bioisosteres of diaryl ethers and can function as replacements methane, ketone, sulfone groups. However, methods to prepare scarce, especially starting from abundant aryl halides. We report the Pd‐catalyzed aryldifluoromethylation halides with aryldifluoromethyl trimethylsilanes (TMSCF 2 Ar). The reaction occurs when catalyst contains a simple, but unusual, dialkylaryl phosphine ligand that promotes transmetallation silane. Computational studies show reductive elimination following low barrier, despite fluorine atoms on α‐carbon, due coordination difluorobenzyl π‐system palladium. co‐development cobalt‐catalyzed synthesis silanes broadened scope process including several applications biologically relevant difluoromethanes.

Язык: Английский

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Bromine radical enhanced stoichiometric pyridylation of alkylarenes and diarylmethanes at room temperature

Organic Chemistry Frontiers, Год журнала: 2022, Номер 10(4), С. 890 - 897

Опубликована: Дек. 23, 2022

Sustainable photoredox catalysis with bromine radical-mediated hydrogen atom transfer enables stoichiometric pyridylation to synthesize a wide range of diarylmethanes and triarylmethanes in good excellent yields.

Язык: Английский

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Electrochemically Driven C4-Selective Decyanoalkylation of Cyanopyridines with Unactivated Alkyl Bromides Enabling C(sp³)–C(sp²) Coupling

Organic Letters, Год журнала: 2023, Номер 25(51), С. 9237 - 9242

Опубликована: Дек. 14, 2023

With cyanopyridines and alkyl bromides as coupling partners, an electrochemically driven C4-selective decyanoalkylation has been established to access diverse 4-alkylpyridines in one step. The reaction proceeds through the single electron reduction/radical–radical tandem process under mild electrolytic conditions, achieving cleavage of C(sp2)–CN bond formation C(sp3)–C(sp2). practicality this protocol is illustrated by no sacrificial anodes, a broad substrate scope, gram-scale synthesis.

Язык: Английский

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Expanding Biocatalysis for Organosilane Functionalization: Enantioselective Nitrene Transfer to Benzylic Si–C–H Bonds

ACS Catalysis, Год журнала: 2023, Номер 14(1), С. 148 - 152

Опубликована: Дек. 16, 2023

Directed evolution has the potential to enable abiological chemistry by engineering natural enzymes function on non-natural substrates. In this study, we expanded repertoire of enzymatic functionalization organosilicon compounds evolving a cytochrome P450 variant for selective amidation organosilanes, resulting in production functionalized α-aminosilanes with remarkable enantioselectivities (up 333 TTN and >99% ee). The evolved enzyme catalyzes nitrene transfer reaction benzylic Si–C–H bonds under aerobic conditions up 125-fold higher yield compared its progenitor, previously unactivated C–H carbon-based molecules.

Язык: Английский

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Access to germasiloxanes and alkynylgermanes mediated by earth-abundant species

Scientific Reports, Год журнала: 2023, Номер 13(1)

Опубликована: Апрель 6, 2023

The reactions between silanols or terminal acetylenes with alkynylgermanes have been accomplished using potassium bis(trimethylsilyl)amide as the catalyst. This strategy has provided an entry point into various organogermanes including germasiloxanes and alkynylgermanes. Remarkably, not only KHMDS but also simple bases such KOH can serve efficient catalysts in this process.

Язык: Английский

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