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Updated: Dec 14, 2025

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Development of a Robust Protocol for the Determination of Weak Acids' pKa Values in DMSO
Sebastian T Jung1, Joachim Podlech1
1Institut für Organische Chemie, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
Abstract:
Two methods for the determination of pKa values of weak acids are described, a direct titration with dimsyl potassium in the presence of an indicator and a back-titration in which an analyte/indicator mixture is deprotonated and then titrated with ammonium chloride. Both methods have been validated by measuring pKa values of compounds, for which values had been determined previously. The back-titration method was applied to measure pKa values of two 1,3-dithiane-derived bissulfoxides and a monosulfone.
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