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Effect of the enamine pyramidalization direction on the reactivity of secondary amine organocatalysts.

ABSTRACT: Chiral secondary amines are valuable catalysts for reactions that proceed through an enamine intermediate. Here, we explored the importance of the pyramidalization direction of the enamine-N on the reactivity of chiral enamines with a combination of computational, NMR spectroscopic, and kinetic experiments. Studies with peptidic catalysts that bear cyclic amines with different ring sizes revealed that endo-pyramidalized enamines are significantly more reactive compared to exo-pyramidalized analogs. The results show that the pyramidalization direction can have a greater effect than n→π* orbital overlap on the reactivity of chiral enamines. The data enabled the development of a catalyst with higher reactivity compared to the parent catalyst.

SUBMITTER: Schnitzer T

PROVIDER: S-EPMC8148379 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Effect of the enamine pyramidalization direction on the reactivity of secondary amine organocatalysts.

Schnitzer Tobias T Möhler Jasper S JS Wennemers Helma H

Chemical science 20200107 7

Chiral secondary amines are valuable catalysts for reactions that proceed through an enamine intermediate. Here, we explored the importance of the pyramidalization direction of the enamine-N on the reactivity of chiral enamines with a combination of computational, NMR spectroscopic, and kinetic experiments. Studies with peptidic catalysts that bear cyclic amines with different ring sizes revealed that endo-pyramidalized enamines are significantly more reactive compared to exo-pyram ...[more]

PMID: 34123288

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