Basicity of a Stable Carbene, 1,3-Di-tert-butylimidazol-2-ylidene, in THF1
- 25 April 2002
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 124 (20) , 5757-5761
- https://doi.org/10.1021/ja025628j
Abstract
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 constants were measured. Homoconjugation was not found in either THF or DMSO. The carbene is effectively more basic in DMSO by several pK units, probably because of hydrogen bonding of 1-H+ to DMSO. Model ab initio computations are consistent with these results.Keywords
This publication has 15 references indexed in Scilit:
- Ion Pair Basicity of Some Amines in THF: Implications for Ion Pair Acidity Scales1Journal of the American Chemical Society, 2000
- Looking for Stable Carbenes: The Difficulty in Starting AnewAccounts of Chemical Research, 1999
- A potentiometric study of acid–base equilibria of substituted pyridines in acetonitrileAnalytica Chimica Acta, 1999
- Extended lithium ion pair indicator scale in tetrahydrofuranCanadian Journal of Chemistry, 1998
- A Bis(carbene)-Proton Complex: Structure of a C-H-C Hydrogen BondJournal of the American Chemical Society, 1995
- Stable carbenes as strong basesJournal of the Chemical Society, Chemical Communications, 1995
- Equilibrium acidities in dimethyl sulfoxide solutionAccounts of Chemical Research, 1988
- Carbon acidity. 73. Conductimetric study of lithium and cesium salts of hydrocarbon acids. A scale of free ion acidities in tetrahydrofuran. Revision of the ion pair scalesJournal of the American Chemical Society, 1988
- Equilibriums involving organic anions in dimethyl sulfoxide and N-methylpyrrolidin-2-one: acidities, ion pairing, and hydrogen bondingThe Journal of Organic Chemistry, 1980
- The Acidities of Weak Acids in Dimethyl Sulfoxide. II. The Hammett Acidity FunctionJournal of the American Chemical Society, 1965