Ru-catalysed C-H arylation of indoles and pyrroles with boronic acids: scope and mechanistic studies.
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.
['Sollert|Carina|C|', 'Devaraj|Karthik|K|', 'Orthaber|Andreas|A|', 'Gates|Paul J|PJ|', 'Pilarski|Lukasz T|LT|']
CH activation catalysis heterocycles reaction mechanisms ruthenium