Surface modification

Pathology

Physical chemistry

Catalysis

Organic chemistry

Chemistry

Indole test

Alternative medicine

Combinatorial chemistry

Carbonyl group

Reactivity (psychology)

Carbene

Thioether

Iridium

Stereochemistry

Medicine

Organic Letters

Site-selective direct functionalization of an indole benzenoid core has been a great challenge due to its inherently poor reactivity. We herein demonstrate an iridium-catalyzed C4-selective acylmethylation of indoles using α-carbonyl sulfoxonium ylides as carbene precursors. This method exhibits high efficiency and broad functional group compatibility. The directing group was easily removed or converted to other functionalities after the catalysis. The potential synthetic utility of the coupling products was highlighted by constructing medium-sized polycyclic indoles.

Thioether-Directed C4-Selective C–H Acylmethylation of Indoles Using α-Carbonyl Sulfoxonium Ylides