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B(C₆F₅)₃-Catalyzed Direct C3 Alkylation of Indoles and Oxindoles.

ABSTRACT: The direct C3 alkylation of indoles and oxindoles is a challenging transformation, and only a few direct methods exist. Utilizing the underexplored ability of triaryl boranes to mediate the heterolytic cleavage of ?-nitrogen C-H bonds in amines, we have developed a catalytic approach for the direct C3 alkylation of a wide range of indoles and oxindoles using amine-based alkylating agents. We also employed this borane-catalyzed strategy in an alkylation-ring opening cascade.

SUBMITTER: Basak S

PROVIDER: S-EPMC7311048 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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B(C6F5)3-Catalyzed Direct C3 Alkylation of Indoles and Oxindoles.

Basak Shyam S Alvarez-Montoya Ana A Winfrey Laura L Melen Rebecca L RL Morrill Louis C LC Pulis Alexander P AP

ACS catalysis 20200409 8

The direct C3 alkylation of indoles and oxindoles is a challenging transformation, and only a few direct methods exist. Utilizing the underexplored ability of triaryl boranes to mediate the heterolytic cleavage of α-nitrogen C-H bonds in amines, we have developed a catalytic approach for the direct C3 alkylation of a wide range of indoles and oxindoles using amine-based alkylating agents. We also employed this borane-catalyzed strategy in an alkylation-ring opening cascade. ...[more]

PMID: 32596025

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