Login for students

Login for employees

Publication detail

Determination of rate constants by ESI-MS: extension of the delayed reactant labeling method
Authors: Váňa Jiří | Petrović Vladimir | Terencio Thibault | Roithová Jana
Year: 2017
Type of publication: ostatní - přednáška nebo poster
Page from-to: nestránkováno
Titles:
Language Name Abstract Keywords
eng Determination of rate constants by ESI-MS: extension of the delayed reactant labeling method In recent years we have focused our attention on development of a new method for determination of rate constants of reactions proceeding in solution by means of ESI-MS.1,2 The Delayed reactant labeling approach is based on mixing of isotopically labeled and unlabeled reactants in different reaction times. The mutual evolution of equivalent, labeled and unlabeled signals in the ESI-MS spectrum reflects the kinetics of the relevant species in solution. We present here an extension of this methodology with employing differently substituted reactants instead of isotopically labeled ones. We have investigated a palladium catalyzed reaction and followed formation of palladium containing complexes. Hence, introduction of substituents with different masses helped to overcome a problem of a signal overlap caused by the rich isotopic pattern of palladium. The different substitution of reactants causes a different ESI response of analogous complexes (i.e. the same concentrations of the given complexes in solution does not automatically lead to the same signals in the ESI-MS spectrum). This problem is accounted for in the method and can be separated out in the extraction of the rate constants. We demonstrate this approach on palladium catalyzed C–H activation reaction of substituted acetanilides. The Hammett analysis of the rate constants obtained by our method for a series of meta and para substituted acetanilides provides the ρ value of -1.4, which is in agreement with values reported for similar C–H activations. Comparison of the results with those obtained from UV-Vis measurements and theoretical calculations shows a nice agreement and were further used for deeper analysis of reaction mechanism. ESI-MS, rate constant, palladium catalyzed reaction

Departments

Other Parts

Map

en.mapy.cz

Services

Popular Links

© 2023 University of Pardubice, Studentská 95, 532 10 Pardubice 2
Phone: +420 466 036 111, 466 036 112, 466 036 113
Webmaster, RSS
Data box ID: f5vj9hu
Accessibility Statement
CC BY-NC-ND 4.0Creative CommonsAttributionNonCommercialNoDerivatives