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Updated: Jun 20, 2026

Measurement of the Potential Rates of Dissimilatory Nitrate Reduction to Ammonium Based on 14NH4+/15NH4+ Analyses via Sequential Conversion to N2O
Published on: October 7, 2020
Suppression of common-ion return by amines: a method to measure rates of fast S(N)1 reactions
Nicolas Streidl1, Anna Antipova, Herbert Mayr
1Department Chemie und Biochemie der Ludwig-Maximilians-Universität München, Germany.
Abstract:
Rate constants for solvolyses of benzhydryl chlorides, which take place on the 10 ms to minute time scale, have been determined in aqueous acetone and acetonitrile by conductometry, using conventional conductometers as well as stopped-flow techniques. Secondary and tertiary amines were used to suppress ion recombination (common-ion return) thus giving access to the ionization rate constants k(1). The observed common-ion rate depressions can be rationalized by the correlation equation for electrophile-nucleophile combinations, log k(20 degrees C) = s(E + N), where electrophiles (here: carbocations) are characterized by the parameter E and nucleophiles (here: chloride anions and solvents) are characterized by N and s.
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