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Saturated oxygen and nitrogen heterocycles via oxidative coupling of alkyltrifluoroborates with alkenols, alkenoic acids and protected alkenylamines.

ABSTRACT: Saturated heterocycles are important components of many bioactive compounds. The method disclosed herein enables a general route to a range of 5-, 6- and 7-membered oxygen and nitrogen heterocycles by coupling potassium alkyltrifluoroborates with heteroatom-tethered alkenes, predominantly styrenes, under copper-catalyzed conditions, in the presence of MnO2. The method was applied to the synthesis of the core of the anti-depressant drug citalopram. The reaction scope and observed reactivity is consistent with a polar/radical mechanism involving intermolecular addition of the alkyl radical to the alkene followed by [Cu(iii)]-facilitated C-O (or C-N) bond forming reductive elimination.

SUBMITTER: Shikora JM

PROVIDER: S-EPMC7003886 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Saturated oxygen and nitrogen heterocycles <i>via</i> oxidative coupling of alkyltrifluoroborates with alkenols, alkenoic acids and protected alkenylamines.

Shikora Jonathan M JM Um Chanchamnan C Khoder Zainab M ZM Chemler Sherry R SR

Chemical science 20190819 40

Saturated heterocycles are important components of many bioactive compounds. The method disclosed herein enables a general route to a range of 5-, 6- and 7-membered oxygen and nitrogen heterocycles by coupling potassium alkyltrifluoroborates with heteroatom-tethered alkenes, predominantly styrenes, under copper-catalyzed conditions, in the presence of MnO<sub>2</sub>. The method was applied to the synthesis of the core of the anti-depressant drug citalopram. The reaction scope and observed react ...[more]

PMID: 32055311

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