The Copper‐Catalyzed C‐3‐Formylation of Indole CH Bonds using Tertiary Amines and Molecular Oxygen

Cu-Catalyzed selective C3-formylation of imidazo[1,2-a]pyridine C–H bonds with DMSO using molecular oxygen

Using the widely available DMSO as the formylation reagent under oxidative conditions, an efficient Cu-catalyzed C3-formylation reaction of imidazo [1,2-a]pyridine C–H bonds to directly generate structurally sophisticated 3-formyl imidazo[1,2-a]pyridine derivatives has been developed.

Friedel–Crafts reaction of indoles with vicinal tricarbonyl compounds generated in situ from 1,3-dicarbonyl compounds and TEMPO: highly selective synthesis of tertiary alcohols

A novel Friedel–Crafts reaction of indoles with vicinal tricarbonyl compounds generated in situ has been developed, forming indolyl tertiary alcohols. The process involves disproportionation of TEMPO, α-oxyamination, N–O bond cleavage and, finally, addition of the indole.

Rhodium-catalyzed annulation between 2-arylimidazo[1,2-a]pyridines and alkynes leading to pyrido[1,2-a]benzimidazole derivatives

A rhodium-catalyzed annulation between 2-arylimidazo[1,2-a]pyridines and alkynes was developed, leading to pyrido[1,2-a]benzimidazole derivatives in moderate to excellent yields.

Copper-mediated tandem reaction of β-ketoesters/ketones with tertiary amines for the synthesis of 2,3-dihydrofurans

A novel synthetic method of 2,3-dihydrofuran using β-ketoester and TMEDA as starting materials has been developed.

An efficient approach to 1,2,3-trisubstituted indole via rhodium catalyzed carbene Csp3–H bond insertion

A method for convenient synthesis of N-alkyl-2-aryl-indole-3-carbaldehyde via carbene C–H bond insertion.

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.

Oxidative cleavage of benzylic C–N bonds under metal-free conditions

An interesting and practical metal-free strategy has been developed for the synthesis of aromatic aldehydes using various N,N-dimethylbenzylamines as starting materials.