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Hemilabile Benzyl Ether Enables ?-C(sp3)-H Carbonylation and Olefination of Alcohols.

ABSTRACT: Pd-catalyzed C(sp3)-H activation of alcohol typically shows ?-selectivity due to the required distance between the chelating atom in the attached directing group and the targeted C-H bonds. Herein we report the design of a hemilabile directing group which exploits the chelation of a readily removable benzyl ether moiety to direct ?- or ?-C-H carbonylation and olefination of alcohols. The utility of this approach is also demonstrated in the late-stage C-H functionalization of ?-estradiol to rapidly prepare desired analogues that required multi-step syntheses with classical methods.

SUBMITTER: Tanaka K

PROVIDER: S-EPMC6776245 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Hemilabile Benzyl Ether Enables γ-C(sp3)-H Carbonylation and Olefination of Alcohols.

Tanaka Keita K Ewing William R WR Yu Jin-Quan JQ

Journal of the American Chemical Society 20190918 39

Pd-catalyzed C(sp3)-H activation of alcohol typically shows β-selectivity due to the required distance between the chelating atom in the attached directing group and the targeted C-H bonds. Herein we report the design of a hemilabile directing group which exploits the chelation of a readily removable benzyl ether moiety to direct γ- or δ-C-H carbonylation and olefination of alcohols. The utility of this approach is also demonstrated in the late-stage C-H functionalization of β-estradi ...[more]

PMID: 31519108

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