Biocatalysis making waves in organic chemistry

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 51(2), P. 594 - 627

Published: Dec. 20, 2021

The many waves of biocatalysis have arisen to solve long-standing synthetic challenges. From industrially applied hydrolases enzymes catalysing selective C–C-bond formation, enables new tools access a plethora compounds.

Language: Английский

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Critical Assessment of the Reducing Ability of Breslow‐type Derivatives and Implications for Carbene‐Catalyzed Radical Reactions**

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(51), P. 26783 - 26789

Published: Oct. 15, 2021

Abstract We report the synthesis of acyl azolium salts stemming from thiazolylidenes C NS , triazolylidenes TN mesoionic carbenes MIC and generation their corresponding radicals enolates, covering about 60 Breslow‐type derivatives. This study highlights role additives in redox behavior these compounds unveils several critical misconceptions radical transformations aldehyde derivatives under N‐heterocyclic carbene catalysis. In particular, reducing ability enolates has been dramatically underestimated case biomimetic . contrast with previous electrochemical studies, we show that catalytic intermediates can transfer electrons to iodobenzene within minutes at room temperature. Enols derived are not previously claimed super electron donors, although enolate powerful agents.

Language: Английский

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Oxidative N‐Heterocyclic Carbene Catalysis

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(4)

Published: Oct. 7, 2022

N-Heterocyclic carbene (NHC) catalysis is a by now consolidated organocatalytic platform for number of synthetic (asymmetric) transformations via diverse reaction modes/intermediates. In addition to the typical umpolung processes involving acyl anion/homoenolate equivalent species, implementation protocols under oxidative conditions greatly expands possibilities this methodology. Oxidative NHC-catalysis allows and oxygenative through specific manipulations Breslow-type species depending upon oxidant used (external or O

Language: Английский

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The green chemistry paradigm in modern organic synthesis

Russian Chemical Reviews, Journal Year: 2023, Volume and Issue: 92(12), P. RCR5104 - RCR5104

Published: Dec. 1, 2023

After the appearance of green chemistry concept, which was introduced in vocabulary early 1990s, its main statements have been continuously developed and modified. Currently, there are 10–12 cornerstones that should form basis for an ideal chemical process. This review analyzes accumulated experience achievements towards design products processes reduce or eliminate use generation hazardous substances. The presents views leading Russian scientists specializing various fields this subject, including homogeneous heterogeneous catalysis, fine basic organic synthesis, electrochemistry, polymer chemistry, based on bio-renewable feedstocks energetic compounds materials. A new approach to quantitative evaluation environmental friendliness by authors is described. <br> bibliography includes 1761.

Language: Английский

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Mesoionic Carbene‐Catalyzed Formyl Alkylation of Aldehydes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(24)

Published: April 18, 2023

Ketones are among the most useful functional groups in organic synthesis, and they commonly encountered a broad range of compounds with various applications. Herein, we describe mesoionic carbene-catalyzed coupling reaction aldehydes non-activated secondary even primary alkyl halides. This metal-free method utilizes deprotonated Breslow intermediates derived from carbenes (MICs), which act as super electron donors induce single-electron reduction mild has substrate scope tolerates many groups, allows to prepare diversity simple ketones well bio-active molecules by late-stage functionalization.

Language: Английский

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Exploring a general mechanistic map on NHC-catalyzed activation/transformation reactions of saturated carboxylic anhydrides

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(11), P. 2670 - 2679

Published: Jan. 1, 2023

A general mechanistic map involving multiple intermediates and pathways has been proposed systematically studied for NHC-catalyzed transformation reactions of saturated carboxylic anhydrides.

Language: Английский

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Mechanism and Origin of Stereoselectivity for the NHC-Catalyzed Desymmetrization Reaction for the Synthesis of Axially Chiral Biaryl Aldehydes

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(5), P. 3133 - 3142

Published: Feb. 15, 2024

Organocatalytic desymmetrization reaction is a powerful tool for constructing axial chirality, but the theoretical study on origin of stereoselectivity still lags behind even now. In this work, N-heterocyclic carbene (NHC)-catalyzed biaryl frameworks synthesis axially chiral aldehydes has been selected and theoretically investigated by using density functional theory (DFT). The fundamental pathway involves several steps, i.e., desymmetrization, formation Breslow oxidation, esterification, NHC regeneration. processes have identified as stereoselectivity-determining rate-determining steps. Further weak interaction analyses proved that C–H···O hydrogen bond C–H···π interactions are responsible stability key stereoselective transition states. This research contributes to understanding nature NHC-catalyzed reactions compounds.

Language: Английский

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1H-1,2,3-Triazol-5-ylidenes as Catalytic Organic Single-Electron Reductants

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(5), P. 2933 - 2938

Published: Jan. 22, 2024

Most of the known single-electron reductants are either metal based reagents, used in a stoichiometric amount, or combination an organic species and photocatalyst. Here we report that 1

Language: Английский

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Taming Highly Enolizable Aldehydes via Enzyme Catalysis for Enantiocomplementary Construction of β-Hydroxyphosphonates

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 17, 2025

Taming highly enolizable aldehydes for catalytic asymmetric C–C coupling with nucleophiles remains an elusive challenge compared to widely explored simple alkyl or aryl aldehydes. Herein, we use ThDP-dependent enzymes realize the direct of 2-phosphonate in situ-generated dynamically reversible (acyl anions). Unlike NHC-mediated reactions that yield complex mixtures multiple adducts, our enzymatic process selectively produces biologically active β-hydroxy phosphonates high yields (up 95%) and excellent enantioselectivities 99% ee). The products can be obtained on gram scales exhibit rich reactivity downstream transformations afford diverse molecules. PfBAL (or its mutant A28G) PaBAL serve as enantiocomplementary pairs, enabling synthesis both product configurations. Mechanistic studies proved entrance directions cavities these two enzyme pairs were distinct, leading acyl anions formed from attacking different orientations.

Language: Английский

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Recent advances of mesoionic N-heterocyclic olefins

Dalton Transactions, Journal Year: 2022, Volume and Issue: 51(24), P. 9191 - 9198

Published: Jan. 1, 2022

This Perspective article highlights the recent development of mesoionic N-heterocyclic olefins (mNHOs), where exo-cyclic olefinic carbon is not bonded to strongly electron-withdrawing groups. The unquenched basicity and nucleophilicity make mNHOs strong σ-donors enable unique reactivity patterns.

Language: Английский

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