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Palladium(II)-Catalyzed Selective Arylation of Tertiary C-H Bonds of Cyclobutylmethyl Ketones Using Transient Directing Groups.

ABSTRACT: We report the first example of selective Pd^II -catalyzed tertiary C-H activation of cyclobutylmethyl ketones using a transient directing group. An electron-deficient 2-pyridone ligand was identified as the optimal external ligand to enable tertiary C-H activation. A variety of cyclobutylmethyl ketones bearing quaternary carbon centers was readily accessed without preinstalling internal directing groups in up to 81 % yield and >95 : 5 regioisomeric ratios of tertiary C-H arylation to β-methylene (β-methyl) or γ-C-H arylation.

SUBMITTER: Cheng JT

PROVIDER: S-EPMC9084898 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Palladium(II)-Catalyzed Selective Arylation of Tertiary C-H Bonds of Cyclobutylmethyl Ketones Using Transient Directing Groups.

Cheng Jin-Tang JT Xiao Li-Jun LJ Qian Shao-Qun SQ Zhuang Zhe Z Liu An A Yu Jin-Quan JQ

Angewandte Chemie (International ed. in English) 20220309 18

We report the first example of selective PdII -catalyzed tertiary C-H activation of cyclobutylmethyl ketones using a transient directing group. An electron-deficient 2-pyridone ligand was identified as the optimal external ligand to enable tertiary C-H activation. A variety of cyclobutylmethyl ketones bearing quaternary carbon centers was readily accessed without preinstalling internal directing groups in up to 81 % yield and >95 : 5 regioisomeric ratios of tertiary C-H arylation to β ...[more]

PMID: 35112447

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