Organocatalytic Reactions Enabled by N-Heterocyclic Carbenes
Chemical ReviewsPublished 20 May 2015Open access
Darrin M. Flanigan, Fedor Romanov‐Michailidis, Nicholas A. White, Tomislav Rovis
Citations2,017
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Chemistry
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Journal of the American Chemical SocietyEnantioselective N-Heterocyclic Carbene-Catalyzed β-Hydroxylation of Enals Using Nitroarenes: An Atom Transfer Reaction That Proceeds via Single Electron Transfer
210 Citations2014Nicholas A. White, Tomislav Rovis
The proposed mechanism involves a single electron transfer event to initiate the reaction followed by radical recombination, which represents a profound mechanistic departure from the established two-electron disconnects in NHC catalysis.
ChemInformCatalytic Generation of Activated Carboxylates from Enals: A Product‐Determining Role for the Base.
208 Citations2005Stephanie S. Sohn, Jeffrey W. Bode
Journal of Organometallic ChemistrySynthesis of chiral triazolinylidene and imidazolinylidene transition metal complexes and first application in asymmetric catalysis
207 Citations2001Dieter Enders, Heike Gielen
Angewandte Chemie International EditionHighly Asymmetric NHC‐Catalyzed Hydroacylation of Unactivated Alkenes
203 Citations2011Isabel Piel, Marc Steinmetz +4 more
Journal of the Chemical Society Perkin Transactions 1Comparison of chiral thiazolium and triazolium salts as asymmetric catalysts for the benzoin condensation
203 Citations1998Roland L. Knight, Finian J. Leeper
Chemical ScienceThe effect of the N-mesityl group in NHC-catalyzed reactions
203 Citations2011Jessada Mahatthananchai, Jeffrey W. Bode
Organic LettersEnantioselective Activation of Stable Carboxylate Esters as Enolate Equivalents <i>via</i> N-Heterocyclic Carbene Catalysts
203 Citations2012Hao Lin, Yu Du +5 more
The first N-Heterocyclic Carbene (NHC) mediated activation of stable carboxylate esters to generate enolate intermediates is disclosed, which undergo enantioselective reactions with α,β-unsaturated imines.
Advanced Synthesis & CatalysisN‐Heterocyclic Carbene‐Catalyzed Enantioselective Annulation of Bromoenal and 1,3‐Dicarbonyl Compounds
202 Citations2011Fang‐Gang Sun, Li‐Hui Sun +1 more
Both enantiomers of the resultant dihydropyranone could be easily obtained by choosing N-heterocyclic carbenes (NHCs) with the same stereocenter but different substituents under the optimized reaction conditions.
Journal of the American Chemical SocietySynthesis of α-Amido Ketones via Organic Catalysis: Thiazolium-Catalyzed Cross-Coupling of Aldehydes with Acylimines
199 Citations2001Jerry A. Murry, Doug E. Frantz +4 more
Advanced Synthesis & CatalysisN‐Heterocyclic Carbene‐Catalyzed Cyclization of Unsaturated Acyl Chlorides and Ketones
196 Citations2011Litao Shen, Pan‐Lin Shao +1 more
Chemical CommunicationsAsymmetric intermolecular Stetter reactions catalyzed by a novel triazolium derived N-heterocyclic carbene
194 Citations2008Dieter Enders, Jianwei Han +1 more
The asymmetric intermolecular Stetter reaction is catalyzed by a novel triazolium salt derived N-heterocyclic carbene leading to 1,4-diketones in moderate to excellent yields and moderate to good enantioselectivities, which could be enhanced by one recrystallization to excellent levels.
Organic LettersOrganocatalytic Tail-to-Tail Dimerization of Olefin: Umpolung of Methyl Methacrylate Mediated by N-Heterocyclic Carbene
193 Citations2011Shin‐ichi Matsuoka, Yoshiya Ota +5 more
Highly selective tail-to-tail dimerization of methyl methacrylate has been realized by an N-heterocyclic carbene catalyst, giving dimethyl 2,5-dimethyl-2-hexenedioate with an E/Z ratio of 95:5 in 86% isolated yield.
Organic LettersEnantioselective Acylation of Secondary Alcohols Catalyzed by Chiral <i>N</i>-Heterocyclic Carbenes
193 Citations2005Taichi Kano, Kouji Sasaki +1 more
The synthetic utility of chiral N-heterocyclic carbenes, which have been used mainly in transition metal-catalyzed reactions as a ligand, was demonstrated by the enantioselective acylation of secondary alcohols.
The Journal of Organic ChemistryAn Acidity Scale of 1,3-Dialkylimidazolium Salts in Dimethyl Sulfoxide Solution
192 Citations2007Yuan Chu, Hui Deng +1 more
Journal of the American Chemical SocietyCyclic Ketimines as Superior Electrophiles for NHC-Catalyzed Homoenolate Additions with Broad Scope and Low Catalyst Loadings
190 Citations2008Michael Rommel, Takeo Fukuzumi +1 more
These findings and supporting studies suggest an alternative, ene-like mechanism rather than the catalytic generation of a catalyst-bound homoenolate equivalent for N-heterocyclic carbene (NHC)-catalyzed annulations with alpha,beta-unsaturated aldehydes to afford highly substituted gamma-lactams.
Angewandte Chemie International EditionN‐Heterocyclic Carbenes: Organocatalysts with Moderate Nucleophilicity but Extraordinarily High Lewis Basicity
187 Citations2011Biplab Maji, Martin Breugst +1 more
Since the first isolation and characterization of stable Nheterocyclic carbenes by Arduengo and co-workers in 1991, these compounds have attracted great interest in various fields of chemistry and are of practical relevance as ligands in metal complexes and as nucleophilic organocatalysts.
Journal of the American Chemical SocietyCatalytic Intramolecular Crossed Aldehyde−Ketone Benzoin Reactions: A Novel Synthesis of Functionalized Preanthraquinones
187 Citations2003Yoshifumi Hachisu, Jeffrey W. Bode +1 more
The first crossed aldehyde-ketone benzoin reaction in excellent yield under mild reaction conditions offers a convenient approach to sophisticated molecular architectures useful for the stereocontrolled construction of polycyclic compounds as well as the fully regiocontrolling synthesis of anthra- and naphthoquinones.
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