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Ru-catalysed C-H arylation of indoles and pyrroles with boronic acids: scope and mechanistic studies.

ABSTRACT: The Ru-catalysed C2-H arylation of indoles and pyrroles by using boronic acids under oxidative conditions is reported. This reaction can be applied to tryptophan derivatives and tolerates a wide range of functional groups on both coupling partners, including bromides and iodides, which can be further derivatised selectively. New indole-based ruthenacyclic complexes are described and investigated as possible intermediates in the reaction. Mechanistic studies suggest the on-cycle intermediates do not possess a para-cymene ligand and that the on-cycle metalation occurs through an electrophilic attack by the Ru centre.

SUBMITTER: Sollert C

PROVIDER: S-EPMC4600241 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Ru-catalysed C-H arylation of indoles and pyrroles with boronic acids: scope and mechanistic studies.

Sollert Carina C Devaraj Karthik K Orthaber Andreas A Gates Paul J PJ Pilarski Lukasz T LT

Chemistry (Weinheim an der Bergstrasse, Germany) 20150217 14

The Ru-catalysed C2-H arylation of indoles and pyrroles by using boronic acids under oxidative conditions is reported. This reaction can be applied to tryptophan derivatives and tolerates a wide range of functional groups on both coupling partners, including bromides and iodides, which can be further derivatised selectively. New indole-based ruthenacyclic complexes are described and investigated as possible intermediates in the reaction. Mechanistic studies suggest the on-cycle intermediates do ...[more]

PMID: 25689052

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