ReviewChemical science2021
Tale of the Breslow intermediate, a central player in N-heterocyclic carbene organocatalysis: then and now.
Review in Chemical science, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers.
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Who cites it
25 citing papers in PubMed.
- Organocatalytic Thioesterification of a Conjugated α,β-Unsaturated Dialdehyde.International journal of molecular sciences · 2026Article
- Review
- Carbon and Heteroatom Activation via N-Heterocyclic Carbene-Bound Dearomative Intermediates for Stereoselective Annulation Reactions.Chemistry (Weinheim an der Bergstrasse, Germany) · 2025Review
- Quantifying Breslow intermediate reactivity in intermolecular Stetter reactions.Chemical science · 2025Article
- Ni/NHC-catalyzed C5-H alkylation and alkenylation of challenging furan(thiophene)-2-carboxaldehydes enabled by recyclable imine protecting group.Communications chemistry · 2025Article
- N-Heterocyclic-Carbene-Catalyzed Imine Umpolung for the Cross-Coupling of Quinoxalin-2-ones with Isatins.JACS Au · 2025Article
- Photochemical reduction of acylimidazolium salts.Beilstein journal of organic chemistry · 2025Article
- Eco-Friendly Functionalization of Ynals with Thiols under Mild Conditions.International journal of molecular sciences · 2024Article
- Organocatalytic synthetic route to esters and their application in hydrosilylation process.Scientific reports · 2024Article
- Computational Design of an Electro-Organocatalyst for Conversion of COThe journal of physical chemistry. A · 2024Article
- Why pyridoxal phosphate could be a functional predecessor of thiamine pyrophosphate and speculations on a primordial metabolism.RSC chemical biology · 2024Review
- Impact of Backbone Substitution on Organocatalytic Activity of Sterically Encumbered NHC in Benzoin Condensation.Molecules (Basel, Switzerland) · 2024Article
- Computational Design of an Electro-Organocatalyst for Conversion of COThe journal of physical chemistry. A · 2024Article
- A (TD-)DFT study on photo-NHC catalysis: photoenolization/Diels-Alder reaction of acid fluorides catalyzed byChemical science · 2023Article
- Oxidative N-Heterocyclic Carbene Catalysis.Chemistry (Weinheim an der Bergstrasse, Germany) · 2023Review
- Rate and equilibrium constants for the addition of triazolium salt derived N-heterocyclic carbenes to heteroaromatic aldehydes.Chemical science · 2022Article
- A Review on Generation and Reactivity of theMolecules (Basel, Switzerland) · 2022Review
- On the Evolutionary History of the Twenty Encoded Amino Acids.Chemistry (Weinheim an der Bergstrasse, Germany) · 2022Review
- Catalyst-Controlled Selectivity Switch in Three-Component Reaction: An NHC-Catalyzed Strategy for the Synthesis of δ-Lactone-Fused Spirobenzofuran-3-ones.Molecules (Basel, Switzerland) · 2022Article
- A Fluoroponytailed NHC-Silver Complex Formed from Vinylimidazolium/AgNOMolecules (Basel, Switzerland) · 2022Article
Corrections and comments
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
N-Heterocyclic carbenes (NHCs) belong to the popular family of organocatalysts used in a wide range of reactions, including that for the synthesis of complex natural products and biologically active compounds. In their organocatalytic manifestation, NHCs are known to impart umpolung reactivity to aldehydes and ketones, which are then exploited in the generation of homoenolate, acyl anion, and enolate equivalents suitable for a plethora of reactions such as annulation, benzoin, Stetter, Claisen rearrangement, cycloaddition, and C-C and C-H bond functionalization reactions and so on. A common thread that runs through these NHC catalyzed reactions is the proposed involvement of an enaminol, also known as the Breslow intermediate, formed by the nucleophilic addition of an NHC to a carbonyl group of a suitable electrophile. In the emerging years of NHC catalysis, enaminol remained elusive and was largely considered a putative intermediate owing to the difficulties encountered in its isolation and characterization. However, in the last decade, synergistic efforts utilizing an array of computational and experimental techniques have helped in gaining important insights into the formation and characterization of Breslow intermediates. Computational studies have suggested that a direct 1,2-proton transfer within the initial zwitterionic intermediate, generated by the action of an NHC on the carbonyl carbon, is energetically prohibitive and hence the participation of other species capable of promoting an assisted proton transfer is more likely. The proton transfer assisted by additives (such as acids, bases, other species, or even a solvent) was found to ease the kinetics of formation of Breslow intermediates. These important details on the formation,
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Registered trials
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