Unlocking the Potential of β-Fragmentation of Aminophosphoranyl Radicals for Sulfonyl Radical Reactions

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(26), P. 14510 - 14518

Published: June 20, 2023

Exploiting β-scission in aminophosphoranyl radicals for radical-mediated transformations has been a longstanding challenge. In this study, we investigated the untapped potential of β-fragmentation by leveraging unique properties P-N bond and substituents P(III) reagents. Our approach carefully considers factors such as cone angle electronic phosphine employs density functional theory (DFT) calculations to probe structural molecular orbital influence. We successfully induced through N-S cleavage under visible light mild conditions, generating range sulfonyl derived from pyridinium salts via photochemical activity electron donor-acceptor (EDA) complexes. This innovative synthetic strategy exhibits broad applicability, including late-stage functionalization, paves way valuable reactions, alkene hydrosulfonylation, difunctionalization, pyridylic C-H sulfonylation.

Language: Английский

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Cyclic Amine Synthesis via Catalytic Radical‐Polar Crossover Cycloadditions

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(18)

Published: Feb. 29, 2024

Abstract The rapid assembly of valuable cyclic amine architectures in a single step from simple precursors has been recognized as an ideal platform term efficiency and sustainability. Although vast number studies regarding synthesis reported, new synthetic disconnection approaches are still high demand. Herein, we report catalytic radical‐polar crossover cycloaddition to triggered primary sulfonamide under photoredox condition. This newly developed disconnection, comparable established approaches, will allow construct β, β‐disubstituted β‐monosubstituted derivatives efficiently. study highlights the unique utility bifunctional reagent, which acts radical precursor nucleophile. open‐shell methodology demonstrates broad tolerance various functional groups, drug natural products economically sustainable fashion.

Language: Английский

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Iron-catalyzed C(sp³)–H phosphorylation via photoinduced LMCT

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(7), P. 2027 - 2032

Published: Jan. 1, 2024

A redox-neutral strategy for C(sp 3 )–H phosphorylation is developed via photoinduced LMCT, where the reaction proceeds through radical addition to chlorophosphines form an R P–Cl˙ and ultimately concluded by single-electron reduction.

Language: Английский

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Rhodium(III)-Catalyzed Anti-Markovnikov Hydroamidation of Unactivated Alkenes Using Dioxazolones as Amidating Reagents

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(49), P. 22426 - 22432

Published: Dec. 1, 2022

The amide is one of the most prevalent functional groups in all pharmaceuticals, and for this reason, reactions that introduce moiety are particular value. Intermolecular hydroamidation alkenes remains an underexplored method synthesis amide-containing compounds. majority procedures exhibit Markovnikov regioselectivity, while current methods anti-Markovnikov somewhat limited to activated alkene substrates or radical processes. Herein, we report a general intermolecular unactivated under mild conditions, utilizing Rh(III) catalysis conjunction with dioxazolone amidating reagents isopropanol as environmentally friendly hydride source. reaction tolerates wide range efficiently converts electron-deficient alkenes, styrenes, 1,1-disubstituted addition their corresponding linear amides. Mechanistic studies reveal reversible rhodium migratory insertion step, leading exquisite selectivity product.

Language: Английский

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Site‐Selective Pyridine C−H Alkylation with Alcohols and Thiols via Single‐Electron Transfer of Frustrated Lewis Pairs

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(51)

Published: Oct. 31, 2022

A unified strategy for the deoxygenative or desulfurative pyridylation of various alcohols and thiols has been developed through a single-electron transfer (SET) process frustrated Lewis pairs (FLPs) derived from pyridinium salts PtBu3 . Mechanistic studies revealed that N-amidopyridinium serve as effective acids formation FLPs with , generated phosphine radical cation ionically couples in situ xanthate, eventually affording alkyl facile β-scission under photocatalyst-free conditions. The reaction efficiency was further accelerated by visible-light irradiation. This method is conceptually appealing using encounter complexes FLP chemistry to promote SET, which provides previously unrecognized opportunity selective heteroarylation diverse range functional groups, even complex settings mild

Language: Английский

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Bioinspired Supercharging of Photoredox Catalysis for Applications in Energy and Chemical Manufacturing

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(10), P. 1423 - 1434

Published: April 26, 2022

ConspectusFor more than a decade, photoredox catalysis has been demonstrating that when photoactive catalysts are irradiated with visible light, reactions occur under milder, cheaper, and environmentally friendlier conditions. Furthermore, this methodology allows for the activation of abundant chemicals into valuable products through novel mechanisms otherwise inaccessible. The approach, however, primarily used pharmaceutical applications, where its implementation highly effective, but typically rudimentary understanding involved in these transformations. From global perspective, manufacture everyday by chemical industry as whole currently accounts 10% total energy consumption generates 7% world's greenhouse gases annually. In context, Bio-Inspired Light-Escalated Chemistry (BioLEC) Energy Frontier Research Center (EFRC) was founded to supercharge approach applications manufacturing aimed at reducing emissions burden, using bioinspired schemes harvest multiple electrons drive endothermically uphill reactions. comprises diverse group researchers expertise includes synthetic chemistry, biophysics, physical engineering. team works together gain deeper mechanistic details while amplifying light-driven methodologies.In Account, we review some major advances understanding, applicability made possible collaborative Center. Combining sophisticated spectroscopic tools photophysics tactics enhanced led development techniques reactivities greatly expand field capabilities. Account is intended highlight how interplay between disciplines can have impact facilitate advance field. For example, such time-resolved dielectric loss (TRDL) pulse radiolysis providing insights not previously available. Hypothesis-driven photocatalyst design thus broadening scope several existing Moreover, bioconjugation approaches triplet–triplet annihilation created new avenues exploration reactivities. Lastly, our multidisciplinary tackling real-world problems inspired efficient methods depolymerization lignin artificial polymers.

Language: Английский

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Copper-Catalyzed Hydroamination: Enantioselective Addition of Pyrazoles to Cyclopropenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(27), P. 14573 - 14580

Published: June 30, 2023

Chiral N-cyclopropyl pyrazoles and structurally related heterocycles are prepared using an earth-abundant copper catalyst under mild reaction conditions with high regio-, diastereo-, enantiocontrol. The observed N2:N1 regioselectivity favors the more hindered nitrogen of pyrazole. Experimental DFT studies support a unique mechanism that features five-centered aminocupration.

Language: Английский

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Cooperative Carbene Photocatalysis for β-Amino Ester Synthesis

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 31, 2023

β-Amino acids are useful building blocks of bioactive molecules, including peptidomimetics and pharmaceutical compounds. The current limited accessibility to β2,2-type amino which bear an α-quaternary center has their use in chemical synthesis biological investigations. Disclosed herein is the development a new N-heterocyclic carbene/photocatalyzed aminocarboxylation olefins, affording β2,2-amino esters with high regioselectivity. generation nitrogen-centered radicals derived from simple imides via sequence deprotonation single-electron oxidation allows for subsequent addition geminal-disubstituted olefins regioselectively. intermediate tertiary then cross-couple stabilized azolium-based radical generated situ efficiently construct quaternary centers. Mechanistic studies, Stern–Volmer fluorescence quenching experiments, support proposed catalytic cycle.

Language: Английский

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Regio- and Enantioselective Nickel-Catalyzed Ipso- and Remote Hydroamination Utilizing Organic Azides as Amino Sources for the Synthesis of Primary Amines

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

Published: Oct. 23, 2024

Primary amines serve as key synthetic precursors to most other

Language: Английский

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Synthesis of Unprotected β‐Arylethylamines by Iron(II)‐Catalyzed 1,2‐Aminoarylation of Alkenes in Hexafluoroisopropanol

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(9)

Published: Dec. 21, 2022

β-Arylethylamines are prevalent structural motifs in molecules exhibiting biological activity. Here we report a sequential one-pot protocol for the 1,2-aminoarylation of alkenes with hydroxylammonium triflate salts and (hetero)arenes. Unlike existing methods, this reaction provides direct entry to unprotected β-arylethylamines remarkable functional group tolerance, allowing key drug-oriented groups be installed two-step process. The use hexafluoroisopropanol as solvent combination an iron(II) catalyst proved essential reaching high-value nitrogen-containing molecules.

Language: Английский

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