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Distal γ-C(sp³ )-H Olefination of Ketone Derivatives and Free Carboxylic Acids.

ABSTRACT: Reported herein is the distal γ-C(sp³ )-H olefination of ketone derivatives and free carboxylic acids. Fine tuning of a previously reported imino-acid directing group and using the ligand combination of a mono-N-protected amino acid (MPAA) and an electron-deficient 2-pyridone were critical for the γ-C(sp³ )-H olefination of ketone substrates. In addition, MPAAs enabled the γ-C(sp³ )-H olefination of free carboxylic acids to form diverse six-membered lactones. Besides alkyl carboxylic acids, benzylic C(sp³ )-H bonds also could be functionalized to form 3,4-dihydroisocoumarin structures in a single step from 2-methyl benzoic acid derivatives. The utility of these protocols was demonstrated in large scale reactions and diversification of the γ-C(sp³ )-H olefinated products.

SUBMITTER: Park HS

PROVIDER: S-EPMC7494175 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Distal γ-C(sp3 )-H Olefination of Ketone Derivatives and Free Carboxylic Acids.

Park Han Seul HS Fan Zhoulong Z Zhu Ru-Yi RY Yu Jin-Quan JQ

Angewandte Chemie (International ed. in English) 20200605 31

Reported herein is the distal γ-C(sp3 )-H olefination of ketone derivatives and free carboxylic acids. Fine tuning of a previously reported imino-acid directing group and using the ligand combination of a mono-N-protected amino acid (MPAA) and an electron-deficient 2-pyridone were critical for the γ-C(sp3 )-H olefination of ketone substrates. In addition, MPAAs enabled the γ-C(sp3 )-H olefination of free carboxylic acids to form diverse six-membered lactones. Bes ...[more]

PMID: 32385966

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