First direct evidence of N-heterocyclic carbene in BMIm acetate ionic liquids. An electrochemical and chemical study on the role of temperature

Cyclic voltammetry provides the first direct evidence of N-heterocyclic carbene (NHC) presence in neat 1-butyl-3-methylimidazolium acetate ionic liquid (BMImAcO) at 120 °C. The NHC existence, proved by its oxidation current in cyclic voltammetry, was confirmed by the formation of a PhCHO–NHC adduct in the pure ionic liquid. The role of the temperature was considered.

[1]  H. -. Kim,et al.  CO2 capture in ionic liquid 1-alkyl-3-methylimidazolium acetate: a concerted mechanism without carbene. , 2017, Physical chemistry chemical physics : PCCP.

[2]  G. Zollo,et al.  N‐Heterocyclic Carbenes and Parent Cations: Acidity, Nucleophilicity, Stability, and Hydrogen Bonding—Electrochemical Study and Ab Initio Calculations , 2016 .

[3]  Oldamur Hollóczki.  Unveiling the peculiar hydrogen bonding behavior of solvated N-heterocyclic carbenes. , 2016, Physical chemistry chemical physics : PCCP.

[4]  Bishnu Prasad Kar,et al.  Reversible Carbene Formation in the Ionic Liquid 1-Ethyl-3-Methylimidazolium Acetate by Vaporization and Condensation. , 2015, Chemphyschem : a European journal of chemical physics and physical chemistry.

[5]  B. Kirchner,et al.  An abnormal N-heterocyclic carbene-carbon dioxide adduct from imidazolium acetate ionic liquids: the importance of basicity. , 2014, Chemistry.

[6]  F. Glorius,et al.  An overview of N-heterocyclic carbenes , 2014, Nature.

[7]  B. Kirchner,et al.  How can a carbene be active in an ionic liquid? , 2014, Chemistry.

[8]  S. Ciprioti,et al.  On the reactivity and stability of electrogenerated N-heterocyclic carbene in parent 1-butyl-3-methyl-1H-imidazolium tetrafluoroborate: Formation and use of N-heterocyclic carbene-CO2 adduct as latent catalyst , 2013 .

[9]  M. Feroci,et al.  An electrochemical methodology for the cyclic CO2 “catch and release”. The role of the electrogenerated N-heterocyclic carbene in BMIm-BF4 , 2013 .

[10]  H. Cattey,et al.  Electrosynthesis of imidazolium carboxylates. , 2013, Organic letters.

[11]  D. J. Nelson,et al.  Quantifying and understanding the electronic properties of N-heterocyclic carbenes. , 2013, Chemical Society reviews.

[12]  B. Kirchner,et al.  Carbene formation in ionic liquids: spontaneous, induced, or prohibited? , 2013, The journal of physical chemistry. B.

[13]  M. Feroci,et al.  Electrolysis of Ionic Liquids. A Possible Keystone for the Achievement of Green Solvent-Catalyst Systems , 2013 .

[14]  K. Scheidt,et al.  A continuum of progress: applications of N-hetereocyclic carbene catalysis in total synthesis. , 2012, Angewandte Chemie.

[15]  Jia‐Xing Lu,et al.  Synthesis of dialkyl carbonates from CO2 and alcohols via electrogenerated N-heterocyclic carbenes , 2012 .

[16]  T. Rovis,et al.  Exploiting Acyl and Enol Azolium Intermediates via NHeterocyclic Carbene Catalyzed Reactions of Alpha-Reducible Aldehydes. , 2012, Advanced synthesis & catalysis.

[17]  Frank Glorius,et al.  Organocatalytic umpolung: N-heterocyclic carbenes and beyond. , 2012, Chemical Society reviews.

[18]  Oldamur Hollóczki,et al.  An organocatalytic ionic liquid. , 2011, Organic & biomolecular chemistry.

[19]  Frank Glorius,et al.  Extending NHC-catalysis: coupling aldehydes with unconventional reaction partners. , 2011, Accounts of chemical research.

[20]  R. Rogers,et al.  Reaction of elemental chalcogens with imidazolium acetates to yield imidazole-2-chalcogenones: direct evidence for ionic liquids as proto-carbenes. , 2011, Chemical communications.

[21]  Oldamur Hollóczki,et al.  Carbenes in ionic liquids , 2010 .

[22]  J. Bode,et al.  An enantioselective Claisen rearrangement catalyzed by N-heterocyclic carbenes. , 2010, Journal of the American Chemical Society.

[23]  D. Enders,et al.  Organocatalysis by N-heterocyclic carbenes. , 2007, Chemical reviews.

[24]  Nicolas Marion,et al.  N-heterocyclic carbenes as organocatalysts. , 2007, Angewandte Chemie.

[25]  Jason A C Clyburne,et al.  Electrochemical reduction of an imidazolium cation: a convenient preparation of imidazol-2-ylidenes and their observation in an ionic liquid. , 2004, Chemical communications.

[26]  Li Xiao,et al.  Electrochemistry of 1-Butyl-3-methyl-1H-imidazolium Tetrafluoroborate Ionic Liquid , 2003 .

[27]  Richard L. Harlow,et al.  A stable crystalline carbene , 1991 .