pKas of the conjugate acids of N-heterocyclic carbenes in water.

  title={pKas of the conjugate acids of N-heterocyclic carbenes in water.},
  author={E. M. Higgins and Je Sherwood and Anita G. Lindsay and James Armstrong and R. Massey and R. Alder and A. O'Donoghue},
  journal={Chemical communications},
  volume={47 5},
pK(a) values of 19.8-28.2 are reported for the conjugate acids of a large series of NHCs in water. The effects of ring size, N-substituent and C(4)-C(5) saturation on pK(a) are discussed. 
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The authors thank the EPSRC (D. E. T., R. S. and C. J. C.) and Durham University (P. Q., D. J. J. and C. R. B.) for funding of this project.
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Ln(II) amido complexes coordinated by ring-expanded N-heterocyclic carbenes - promising catalysts for olefin hydrophosphination.
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A catalytic intramolecular nitrene insertion into a copper(i)-N-heterocyclic carbene bond yielding fused nitrogen heterocycles.
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Imidazolium salts were conveniently prepared by direct aryl quaternization using arylboronic acids. This process features the tolerance of a broad range of functional groups and excellentExpand
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The basicity of 1,3-di-tert-butylimidazol-2-ylidene (1) was measured in THF against three hydrocarbon indicators. Both ion pairs and free ions were found and the corresponding equilibrium constantsExpand
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Complexation of stable carbenes with alkali metals
Stable diaminocarbenes, including imidazol-2-ylidenes, undergo complexation with lithium, sodium and potassium species; the crystal structure of a complex ofExpand
Chiral N-heterocyclic carbene-transition metal complexes in asymmetric catalysis
Syntheses and applications of chiral N-heterocyclic carbenes are reviewed. The common features of successful enantioselective catalysts are identified, and the outlook for further investigations isExpand
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  • O. Kühl
  • Chemistry, Medicine
  • Chemical Society reviews
  • 2007
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Equilibrium acidities of 16 1,3-dialkylimidazolium-type ionic liquid (IL) molecules (1-16) were systematically measured by the overlapping indicator method at 25 degrees C in dimethyl sulfoxideExpand
Formation and Stability of Enolates of Acetamide and Acetate Anion: An Eigen Plot for Proton Transfer at α-Carbonyl Carbon
Second-order rate constants were determined in D2O for deprotonation of acetamide, N,N-dimethylacetamide, and acetate anion by deuterioxide ion and for deprotonation of acetamide by quinuclidine. TheExpand
Experimental and Computational Determination of the Effect of the Cyano Group on Carbon Acidity in Water
Rate constants kDO (M-1 s-1) for the deprotonation of cyanoalkanes by deuterioxide ion in D2O at 25 °C were determined by following the appearance of the deuterium-labeled cyanoalkanes by 1H NMR.Expand