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Metal-free ?-amination of secondary amines: computational and experimental evidence for azaquinone methide and azomethine ylide intermediates.

ABSTRACT: We have performed a combined computational and experimental study to elucidate the mechanism of a metal-free ?-amination of secondary amines. Calculations predicted azaquinone methides and azomethine ylides as the reactive intermediates and showed that iminium ions are unlikely to participate in these transformations. These results were confirmed by experimental deuterium-labeling studies and the successful trapping of the postulated azomethine ylide and azaquinone methide intermediates. In addition, computed barrier heights for the rate-limiting step correlate qualitatively with experimental findings.

SUBMITTER: Dieckmann A

PROVIDER: S-EPMC3654248 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Metal-free α-amination of secondary amines: computational and experimental evidence for azaquinone methide and azomethine ylide intermediates.

Dieckmann Arne A Richers Matthew T MT Platonova Alena Yu AY Zhang Chen C Seidel Daniel D Houk K N KN

The Journal of organic chemistry 20130402 8

We have performed a combined computational and experimental study to elucidate the mechanism of a metal-free α-amination of secondary amines. Calculations predicted azaquinone methides and azomethine ylides as the reactive intermediates and showed that iminium ions are unlikely to participate in these transformations. These results were confirmed by experimental deuterium-labeling studies and the successful trapping of the postulated azomethine ylide and azaquinone methide intermediates. In addi ...[more]

PMID: 23517448

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