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Ligand-Enabled β-Methylene C(sp³ )-H Arylation of Masked Aliphatic Alcohols.

ABSTRACT: Despite recent advances, reactivity and site-selectivity remain significant obstacles for the practical application of C(sp³ )-H bond functionalization methods. Here, we describe a system that combines a salicylic-aldehyde-derived L,X-type directing group with an electron-deficient 2-pyridone ligand to enable the β-methylene C(sp³ )-H arylation of aliphatic alcohols, which has not been possible previously. Notably, this protocol is compatible with heterocycles embedded in both alcohol substrates and aryl coupling partners. A site- and stereo-specific annulation of dihydrocholesterol and the synthesis of a key intermediate of englitazone illustrate the practicality of this method.

SUBMITTER: Xia G

PROVIDER: S-EPMC7219561 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Ligand-Enabled β-Methylene C(sp3 )-H Arylation of Masked Aliphatic Alcohols.

Xia Guoqin G Zhuang Zhe Z Liu Luo-Yan LY Schreiber Stuart L SL Melillo Bruno B Yu Jin-Quan JQ

Angewandte Chemie (International ed. in English) 20200311 20

Despite recent advances, reactivity and site-selectivity remain significant obstacles for the practical application of C(sp3 )-H bond functionalization methods. Here, we describe a system that combines a salicylic-aldehyde-derived L,X-type directing group with an electron-deficient 2-pyridone ligand to enable the β-methylene C(sp3 )-H arylation of aliphatic alcohols, which has not been possible previously. Notably, this protocol is compatible with heterocycles embedded in b ...[more]

PMID: 32050036

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