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Radical α-addition involved electrooxidative [3 + 2] annulation of phenols and electron-deficient alkenes.

ABSTRACT: An electrooxidative [3 + 2] annulation of phenols and electron-deficient alkenes for the synthesis of C3-functionalized 2-aryl-2,3-dihydrobenzofuran derivatives was achieved. The ring construction starts by a unique α-addition of carbon radicals derived from anodic oxidation of phenols to electron-deficient alkenes. The subsequent anodic oxidation of the resulting alkyl radical intermediates followed by trapping with the phenolic hydroxy group assembles the 2,3-dihydrobenzofuran core. Such a pathway enables the installation of various electrophilic functionalities including alkoxycarbonyl, alkylaminocarbonyl, trifluoromethyl, and cyano groups at the C-3 of the 2,3-dihydrobenzofuran framework, which is unattainable by other intermolecular reactions. The application of this method for a rapid synthesis of a bioactive natural product is demonstrated.

SUBMITTER: Zhao Q

PROVIDER: S-EPMC8152790 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Radical α-addition involved electrooxidative [3 + 2] annulation of phenols and electron-deficient alkenes.

Zhao Qiang Q Jin Ji-Kang JK Wang Jie J Zhang Feng-Lian FL Wang Yi-Feng YF

Chemical science 20200323 15

An electrooxidative [3 + 2] annulation of phenols and electron-deficient alkenes for the synthesis of C3-functionalized 2-aryl-2,3-dihydrobenzofuran derivatives was achieved. The ring construction starts by a unique α-addition of carbon radicals derived from anodic oxidation of phenols to electron-deficient alkenes. The subsequent anodic oxidation of the resulting alkyl radical intermediates followed by trapping with the phenolic hydroxy group assembles the 2,3-dihydrobenzofuran core. Such a pat ...[more]

PMID: 34122860

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