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Boron-mediated directed aromatic C-H hydroxylation.

ABSTRACT: Transition metal-catalysed C-H hydroxylation is one of the most notable advances in synthetic chemistry during the past few decades and it has been widely employed in the preparation of alcohols and phenols. The site-selective hydroxylation of aromatic C-H bonds under mild conditions, especially in the context of substituted (hetero)arenes with diverse functional groups, remains a challenge. Here, we report a general and mild chelation-assisted C-H hydroxylation of (hetero)arenes mediated by boron species without the use of any transition metals. Diverse (hetero)arenes bearing amide directing groups can be utilized for ortho C-H hydroxylation under mild reaction conditions and with broad functional group compatibility. Additionally, this transition metal-free strategy can be extended to synthesize C7 and C4-hydroxylated indoles. By utilizing the present method, the formal synthesis of several phenol intermediates to bioactive molecules is demonstrated.

SUBMITTER: Lv J

PROVIDER: S-EPMC7067857 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Boron-mediated directed aromatic C-H hydroxylation.

Lv Jiahang J Zhao Binlin B Yuan Yu Y Han Ying Y Shi Zhuangzhi Z

Nature communications 20200312 1

Transition metal-catalysed C-H hydroxylation is one of the most notable advances in synthetic chemistry during the past few decades and it has been widely employed in the preparation of alcohols and phenols. The site-selective hydroxylation of aromatic C-H bonds under mild conditions, especially in the context of substituted (hetero)arenes with diverse functional groups, remains a challenge. Here, we report a general and mild chelation-assisted C-H hydroxylation of (hetero)arenes mediated by bor ...[more]

PMID: 32165636

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