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A denitrogenative palladium-catalyzed cascade for regioselective synthesis of fluorenes.

ABSTRACT: We herein report a denitrogenative palladium-catalyzed cascade for the modular and regioselective synthesis of polysubstituted fluorenes. Hydrazone facilitates the Pd(ii) to Pd(iv) oxidative addition in a Catellani pathway and is also the methylene synthon in the proposed reaction. Aryl iodides and 2-bromoarylaldehyde hydrazones undergo a norbornene-controlled tandem reaction sequence to give a broad scope of fluorenes in the presence of a palladium catalyst. The method described is scalable and adaptable to a three-component reaction with in situ generation of the hydrazone group. Preliminary mechanistic investigations have been conducted.

SUBMITTER: Fu WC

PROVIDER: S-EPMC8148384 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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A denitrogenative palladium-catalyzed cascade for regioselective synthesis of fluorenes.

Fu Wai Chung WC Kwong Fuk Yee FY

Chemical science 20191217 5

We herein report a denitrogenative palladium-catalyzed cascade for the modular and regioselective synthesis of polysubstituted fluorenes. Hydrazone facilitates the Pd(ii) to Pd(iv) oxidative addition in a Catellani pathway and is also the methylene synthon in the proposed reaction. Aryl iodides and 2-bromoarylaldehyde hydrazones undergo a norbornene-controlled tandem reaction sequence to give a broad scope of fluorenes in the presence of a palladium catalyst. The method described is scalable and ...[more]

PMID: 34123265

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