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P^III /P^V =O Catalyzed Cascade Synthesis of N-Functionalized Azaheterocycles.

ABSTRACT: An organocatalytic method for the modular synthesis of diverse N-aryl and N-alkyl azaheterocycles (indoles, oxindoles, benzimidazoles, and quinoxalinediones) is reported. The method employs a small-ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) and a hydrosilane reductant to drive the conversion of ortho-functionalized nitroarenes into azaheterocycles through sequential intermolecular reductive C-N cross coupling with boronic acids, followed by intramolecular cyclization. This method enables the rapid construction of azaheterocycles from readily available building blocks, including a regiospecific approach to N-substituted benzimidazoles and quinoxalinediones.

SUBMITTER: Nykaza TV

PROVIDER: S-EPMC7054160 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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PIII /PV =O Catalyzed Cascade Synthesis of N-Functionalized Azaheterocycles.

Nykaza Trevor V TV Li Gen G Yang Junyu J Luzung Michael R MR Radosevich Alexander T AT

Angewandte Chemie (International ed. in English) 20200129 11

An organocatalytic method for the modular synthesis of diverse N-aryl and N-alkyl azaheterocycles (indoles, oxindoles, benzimidazoles, and quinoxalinediones) is reported. The method employs a small-ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) and a hydrosilane reductant to drive the conversion of ortho-functionalized nitroarenes into azaheterocycles through sequential intermolecular reductive C-N cross coupling with boronic acids, followed by intramolecular cy ...[more]

PMID: 31869510

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