Direct Regioselective Oxidative Cross-Coupling of Indoles with Methyl Ketones: A Novel Route to C3-Dicarbonylation of Indoles

The first C3-dicarbonylation of indoles was realized through direct oxidative cross-coupling of indoles with methyl ketones in the presence of molecular iodine and pyrrolidine. This reaction constructed a highly efficient indolyl diketones scaffold, which might be regarded as a useful biological and pharmacological tool in the exploration of therapeutic A2BAR modulators. The use of inexpensive molecular iodine and pyrrolidine and a broad substrate scope make this protocol very practical. Preliminary mechanistic studies indicate that two paths are involved in this process.