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Hydrogen and proton exchange at carbon. Imbalanced transition state and mechanism crossover.

ABSTRACT: A recent remarkable study of the C-H oxidation of substituted fluorenyl-benzoates together with the transfer of a proton to an internal receiving group by means of electron transfer outer-sphere oxidants, in the noteworthy absence of hydrogen-bonding interactions, is taken as an example to uncover the existence of a mechanism crossover, making the reaction pass from a CPET pathway to a PTET pathway as the driving force of the global reaction decreases. This was also the occasion to stress that considerations based on "imbalanced" or "asynchronous" transition states cannot replace activation/driving force models based on the quantum mechanical treatment of both electrons and transferring protons.

SUBMITTER: Costentin C

PROVIDER: S-EPMC8146334 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Hydrogen and proton exchange at carbon. Imbalanced transition state and mechanism crossover.

Costentin Cyrille C Savéant Jean-Michel JM

Chemical science 20191129 4

A recent remarkable study of the C-H oxidation of substituted fluorenyl-benzoates together with the transfer of a proton to an internal receiving group by means of electron transfer outer-sphere oxidants, in the noteworthy absence of hydrogen-bonding interactions, is taken as an example to uncover the existence of a mechanism crossover, making the reaction pass from a CPET pathway to a PTET pathway as the driving force of the global reaction decreases. This was also the occasion to stress that c ...[more]

PMID: 34084355

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