New Redox Strategies in Organic Synthesis by Means of Electrochemistry and Photochemistry

ACS Central Science, Год журнала: 2020, Номер 6(8), С. 1317 - 1340

Опубликована: Июль 16, 2020

As the breadth of radical chemistry grows, new means to promote and regulate single-electron redox activities play increasingly important roles in driving modern synthetic innovation. In this regard, photochemistry electrochemistry-both considered as niche fields for decades-have seen an explosive renewal interest recent years gradually have become a cornerstone organic chemistry. Outlook article, we examine current state-of-the-art areas electrochemistry photochemistry, well nascent area electrophotochemistry. These techniques employ external stimuli activate molecules imbue privileged control reaction progress selectivity that is challenging traditional chemical methods. Thus, they provide alternative entries known reactive intermediates enable distinct strategies were previously unimaginable. Of many hallmarks, electro- are often classified "green" technologies, promoting reactions under mild conditions without necessity potent wasteful oxidants reductants. This reviews most growth these with special emphasis on conceptual advances given rise enhanced accessibility tools trade.

Язык: Английский

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Enantioselective Photochemical Reactions Enabled by Triplet Energy Transfer

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 1626 - 1653

Опубликована: Июль 6, 2021

For molecules with a singlet ground state, the population of triplet states is mainly possible (a) by direct excitation and subsequent intersystem crossing or (b) energy transfer from an appropriate sensitizer. The latter scenario enables catalytic photochemical reaction in which sensitizer adopts role catalyst undergoing several cycles photon absorption to substrate. If product molecule triplet-sensitized process chiral, this can proceed enantioselectively upon judicious choice chiral An enantioselective also occur dual approach which, apart achiral sensitizer, second activates substrate toward sensitization. Although idea reactions via intermediates has been pursued for more than 50 years, notable selectivities exceeding 90% enantiomeric excess (ee) have only realized past decade. This review attempts provide comprehensive survey on various were rendered

Язык: Английский

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Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Год журнала: 2022, Номер 122(6), С. 5842 - 5976

Опубликована: Янв. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Язык: Английский

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Synthesis of rare sugar isomers through site-selective epimerization

Nature, Год журнала: 2020, Номер 578(7795), С. 403 - 408

Опубликована: Янв. 15, 2020

Язык: Английский

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Challenges and Opportunities in Multicatalysis

ACS Catalysis, Год журнала: 2021, Номер 11(7), С. 3891 - 3915

Опубликована: Март 15, 2021

Multicatalysis is an emerging field targeting the development of efficient catalytic transformations to quickly convert relatively simple starting materials into more complex value-added products. Within multicatalytic processes either multiple catalysts execute single reactions or precise sequences occur in a "one-pot" fashion. Attractively, protocols not only enable that are inaccessible through classic approaches but also able significantly reduce time, waste, and cost synthetic processes, making organic synthesis resources efficient. In this Perspective article, we review different strategies multicatalysis bring distinct challenges opportunities. We divide overarching three main categories: cooperative, domino, relay catalysis. Each category described along with representative examples highlight its features. Special emphasis dedicated catalysis, which further discussed subcategories. Lastly, provide analysis systems incorporate higher levels complexity underscore potential systems.

Язык: Английский

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Boron-enabled geometric isomerization of alkenes via selective energy-transfer catalysis

Science, Год журнала: 2020, Номер 369(6501), С. 302 - 306

Опубликована: Июль 17, 2020

An E-Z boron swivel Compounds with carbon-carbon double bonds can form two distinct isomers, depending on whether the heaviest substituents both carbons lie same side (labeled Z) or diagonally across from each other E). Molloy et al. present a convenient method to reorient that bear and carbonyl substituents. When they are opposed, stay in plane, bond is easily swiveled by photosensitization. However, once as carbonyl, rotates out of plane further sensitization inhibited. Science this issue p. 302

Язык: Английский

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Exploiting attractive non-covalent interactions for the enantioselective catalysis of reactions involving radical intermediates

Nature Chemistry, Год журнала: 2020, Номер 12(11), С. 990 - 1004

Опубликована: Окт. 19, 2020

Язык: Английский

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Enantioselective radical C–H amination for the synthesis of β-amino alcohols

Nature Chemistry, Год журнала: 2020, Номер 12(8), С. 697 - 704

Опубликована: Июнь 22, 2020

Язык: Английский

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Asymmetric Catalysis Mediated by Synthetic Peptides, Version 2.0: Expansion of Scope and Mechanisms

Chemical Reviews, Год журнала: 2020, Номер 120(20), С. 11479 - 11615

Опубликована: Сен. 24, 2020

Low molecular weight synthetic peptides have been demonstrated to be effective catalysts for an increasingly wide array of asymmetric transformations. In many cases, these peptide-based enabled novel multifunctional substrate activation modes and unprecedented selectivity manifolds. These features, along with their ease preparation, modular tunable structures, often biomimetic attributes make well-suited as chiral broad interest. Many examples peptide-catalyzed reactions appeared in the literature since last survey this field

Язык: Английский

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Two unequally redundant "helper" immune receptor families mediate Arabidopsis thaliana intracellular "sensor" immune receptor functions

PLoS Biology, Год журнала: 2020, Номер 18(9), С. e3000783 - e3000783

Опубликована: Сен. 14, 2020

Plant nucleotide-binding (NB) leucine-rich repeat (LRR) receptor (NLR) proteins function as intracellular immune receptors that perceive the presence of pathogen-derived virulence (effectors) to induce responses. The 2 major types plant NLRs "sense" pathogen effectors differ in their N-terminal domains: these are Toll/interleukin-1 resistance (TIR) domain-containing (TNLs) and coiled-coil (CC) (CNLs). In many angiosperms, RESISTANCE TO POWDERY MILDEW 8 (RPW8)-CC domain containing NLR (RNL) subclass CNLs is encoded by gene families, ACTIVATED DISEASE 1 (ADR1) N REQUIREMENT GENE (NRG1), act "helper" during multiple sensor NLR-mediated Despite important role immunity, knowledge specific, redundant, synergistic functions helper RNLs limited. We demonstrate ADR1 NRG1 families an unequally redundant manner basal resistance, effector-triggered immunity (ETI) regulation defense expression. define RNL redundancy ETI conferred some TNLs against virulent pathogens. that, Arabidopsis thaliana, contribute specific initiated TNLs. Time-resolved whole genome expression profiling revealed "classical" trigger similar transcriptome changes, suggesting like other mediate downstream activation. Together, our genetic data confirm fully required for TNL signaling, can also support activation CNL-mediated ETI.

Язык: Английский

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