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Late-stage and strain-accelerated oxidation enabled synthesis of haouamine A.

ABSTRACT: Herein we report a new synthetic entry to the strained cyclophane alkaloid natural product, haouamine A. The successful strategy featured a rhodium-catalyzed diazo-insertion reaction to install the all-carbon quaternary center and a rhodium-catalyzed intramolecular aziridination reaction to establish the nitrogen-bearing stereocenter, of the target molecule. Most notably, a late-stage, site-selective and strain-accelerated oxidation of a "deoxygenated" macrocyclic intermediate was successfully implemented, and in doing so provided a novel solution to the infamous biphenol cyclophane system of haouamine A.

SUBMITTER: Park KHK

PROVIDER: S-EPMC7499817 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Late-stage and strain-accelerated oxidation enabled synthesis of haouamine A.

Park Kun Ho Kenny KHK Rizzo Antonio A Chen David Y-K DY

Chemical science 20200624 31

Herein we report a new synthetic entry to the strained cyclophane alkaloid natural product, haouamine A. The successful strategy featured a rhodium-catalyzed diazo-insertion reaction to install the all-carbon quaternary center and a rhodium-catalyzed intramolecular aziridination reaction to establish the nitrogen-bearing stereocenter, of the target molecule. Most notably, a late-stage, site-selective and strain-accelerated oxidation of a "deoxygenated" macrocyclic intermediate was successfully i ...[more]

PMID: 33033612

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