Recent Advances in Minisci‐Type Reactions

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(39), С. 13666 - 13699

Опубликована: Март 20, 2019

Abstract Reactions that involve the addition of carbon‐centered radicals to basic heteroarenes, followed by formal hydrogen atom loss, have become widely known as Minisci‐type reactions. First developed into a useful synthetic tool in late 1960s Minisci, this reaction type has been constant use over last half century chemists seeking functionalize heterocycles rapid and direct manner, avoiding need for de novo heterocycle synthesis. Whilst originally protocols radical generation remain active today, they joined recent years new array strategies allow wider variety precursors often operate under milder more benign conditions. The surge interest transformations based on free reactivity meant numerous choices are now available chemist looking utilize reaction. Radical‐generation methods photoredox catalysis electrochemistry approaches which thermal cleavage or situ reactive precursors. This review will cover remarkably large body literature appeared topic decade an attempt provide guidance chemist, well perspective both challenges overcome those still remain. As logical classification advances nature precursor, with most concerned, control various selectivity aspects associated reactions also be discussed.

Язык: Английский

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Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Год журнала: 2023, Номер 123(8), С. 4237 - 4352

Опубликована: Янв. 24, 2023

The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C–H functionalization approaches that make use low energy photons as a controllable source. Compared to traditional strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- chemoselectivities. Merging compelling benefits with workflow offers potentially unmatched arsenal tackle drug development campaigns beyond. This Review highlights photocatalytic strategies small-molecule drugs, agrochemicals, natural products, classified according targeted bond newly formed one. Emphasis is devoted identifying, describing, comparing main mechanistic scenarios. draws critical comparison between established ionic chemistry photocatalyzed radical-based manifolds. aims establish current state-of-the-art illustrate key unsolved challenges be addressed in future. authors aim introduce general readership functionalization, specialist practitioners evaluation methodologies, potential for improvement, future uncharted directions.

Язык: Английский

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Single Electron Transfer-Induced Redox Processes Involving N-(Acyloxy)phthalimides

ACS Catalysis, Год журнала: 2021, Номер 11(3), С. 1640 - 1683

Опубликована: Янв. 20, 2021

The past decade has witnessed the emergence of N-(acyloxy)phthalimides (NHPI esters) and its derivatives at forefront synthetic methods facilitating construction diverse molecular frameworks from readily available carboxylic acid feedstock. NHPI esters are predisposed to undergo reductive fragmentation via a single electron transfer (SET) process under thermal, photochemical, or electrochemical conditions generate corresponding carbon- nitrogen-centered radicals that participate in multitude transformations forge carbon–carbon carbon–heteroatom bonds. chemistry involving received broad applicability not only well-designed cascade annulations but also medicinal natural product synthesis. This comprehensive Review, broadly categorized according nature bond formation, details progress made this field since initial discovery by providing representative examples with mechanistic details, an emphasis on challenges future directions.

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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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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Photoelectrochemical Asymmetric Catalysis Enables Direct and Enantioselective Decarboxylative Cyanation

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(44), С. 20201 - 20206

Опубликована: Окт. 31, 2022

The development of efficient and sustainable methods for decarboxylative transformations is great importance due to the ease availability nontoxicity carboxylic acids. Despite tremendous efforts in this area, it remains challenging develop enantioselective direct from Herein we disclose a photoelectrocatalytic method cyanation. photoelectrochemical reactions convert acids enantioenriched nitriles by employing cerium/copper relay catalysis with cerium salt catalytic decarboxylation chiral copper complex stereoselective C-CN formation.

Язык: Английский

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Catalytic Asymmetric Construction of Axially and Centrally Chiral Heterobiaryls by Minisci Reaction

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(13), С. 6040 - 6049

Опубликована: Март 24, 2022

Axially chiral biaryls and heterobiaryls constitute the most represented subclass of atropisomers with prevalence in natural products, bioactive compounds, privileged ligand/catalysts, optically pure materials. Despite many ionic protocols for their construction, radical-based variants represent another highly desirable intriguing strategy but are far less developed. Moreover, efficient synthesis axially heterobiaryl molecules, especially ones having multiple heteroatoms other types elements, through radical routes remains extremely limited. We herein disclose first catalytic asymmetric, metal-free construction centrally by Minisci reaction 5-arylpyrimidines α-amino acid-derived redox-active esters. This is enabled use 4CzIPN as an organic photoredox catalyst conjunction a phosphoric acid catalyst. The achieved variety interesting featuring union α-branched amine generally excellent regio-, diastereo-, enantioselectivity (up to 82% yield; >19:1 dr; >99% ee). finding also builds up new platform development desymmetrization methods via radical-involved atroposelective functionalization at heteroarene prochiral heterobiaryls.

Язык: Английский

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Enantioselective [2π + 2σ] Cycloadditions of Bicyclo[1.1.0]butanes with Vinylazaarenes through Asymmetric Photoredox Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(12), С. 8372 - 8380

Опубликована: Март 18, 2024

Here we present a highly enantioselective [2π + 2σ] photocycloaddition of bicyclo[1.1.0]butanes (BCBs). The reaction uses variety vinylazaarenes as partners and is catalyzed by polycyclic aromatic hydrocarbon (PAH)-containing chiral phosphoric acid bifunctional photosensitizer. A wide array pharmaceutically important bicyclo[2.1.1]hexane (BCH) derivatives have been synthesized with high yields, enantioselectivity, diastereoselectivity. In addition to the diverse 1-ketocarbonyl-3-substituted BCBs, α/β-substituted are compatible such an unprecedented photoredox catalytic pathway, resulting in successful assembly all-carbon quaternary stereocenter or two adjacent tertiary stereocenters on product.

Язык: Английский

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Asymmetric Synthesis of Heterocyclic γ‐Amino‐Acid and Diamine Derivatives by Three‐Component Radical Cascade Reactions

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(44), С. 15803 - 15807

Опубликована: Сен. 6, 2019

Abstract An enantioselective three‐component radical reaction of quinolines or pyridines with enamides and α‐bromo carbonyl compounds by dual photoredox chiral Brønsted acid catalysis is presented. A range valuable γ‐amino‐acid derivatives are accessible in high chemo‐, regio‐, enantioselectivity from simple, readily available starting materials under mild conditions. Using the same strategy, asymmetric synthesis 1,2‐diamine also reported.

Язык: Английский

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Beyond Friedel and Crafts: Directed Alkylation of C−H Bonds in Arenes

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(22), С. 7202 - 7236

Опубликована: Авг. 14, 2018

Abstract Alkylation of arenes is one the most fundamental transformations in chemical synthesis and leads to privileged scaffolds many areas science. Classical methods for introduction alkyl groups are mostly based on Friedel–Crafts reaction, radical additions, metalation, or prefunctionalization arene: these methods, however, suffer from limitations scope, efficiency, selectivity. Moreover, they innate reactivity starting arene, favoring alkylation at a certain position rendering chains other positions much more challenging. This can be addressed by use directing group that facilitates, presence metal catalyst, regioselective C−H bond. These directed alkylations bonds will comprehensively summarized this Review.

Язык: Английский

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