AI Article Synopsis
- - A study was conducted on various triazolium salts to measure their acidity, specifically their pKa values, in DMSO at 25 °C using a method involving bracketing indicators.
- - The research focused on how different structural changes affected the acidity of the triazolium cation, with an emphasis on electronic properties determined by Hammett σ parameters.
- - Unique findings include the first reported pKa value for an azolium salt that produces a mesionic carbene, which aids in selecting suitable bases for deprotonating these salts and linking pKa values to the reactivity of the resulting carbenes.
Article Abstract
A series of triazolium salts, selected for their varying electronic and steric properties, were prepared and their pKa values were determined in DMSO at 25 °C using the bracketing indicator method. The effect of each systematic structural variation upon the acidity of the triazolium cation has been considered, in particular examining the effects of systematically altering electronic properties, quantified through the use of Hammett σ parameters. The first pKa value for an azolium salt that generates a mesionic carbene is also reported. These new data allow for the selection of appropriate bases for the deprotonation of such triazolium salts and the potential to correlate the pKa values determined herein with the nucleophilicity of the corresponding carbenes.
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