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Transient and intermediate carbocations in ruthenium tetroxide oxidation of saturated rings.

ABSTRACT: The ruthenium tetroxide-mediated oxidation of cyclopentane, tetrahydrofuran, tetrahydrothiophene and N-substituted pyrrolidines has been studied computationally by DFT and topological (analysis of the electron localization function, ELF) methods. In agreement with experimental observations and previous DFT calculations, the rate-limiting step of the reaction takes place through a highly asynchronous (3 + 2) concerted cycloaddition through a single transition structure (one kinetic step). The ELF analysis identifies the reaction as a typical one-step-two-stages process and corroborates the existence of a transient carbocation. In the case of pyrrolidines, the carbocation is completely stabilized as an energy minimum in the form of an iminium ion and the reaction takes place in two steps.

SUBMITTER: Pedron M

PROVIDER: S-EPMC6633598 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Transient and intermediate carbocations in ruthenium tetroxide oxidation of saturated rings.

Pedrón Manuel M Legnani Laura L Chiacchio Maria-Assunta MA Caramella Pierluigi P Tejero Tomás T Merino Pedro P

Beilstein journal of organic chemistry 20190711

The ruthenium tetroxide-mediated oxidation of cyclopentane, tetrahydrofuran, tetrahydrothiophene and <i>N</i>-substituted pyrrolidines has been studied computationally by DFT and topological (analysis of the electron localization function, ELF) methods. In agreement with experimental observations and previous DFT calculations, the rate-limiting step of the reaction takes place through a highly asynchronous (3 + 2) concerted cycloaddition through a single transition structure (one kinetic step). ...[more]

PMID: 31354874

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