Rhodium(III)‐Catalyzed Oxidative CH and NH/OH Annulation

Abstract

Nitrogen and oxygen‐containing heterocycles are important core structures in pharmaceutical, agrochemicals, and functional organic materials. The rhodium(III)‐catalyzed oxidative CH and NH/OH annulation reactions of aromatic substrates with alkynes, alkenes, carbene precursors, and so on enable the synthesis of these important heterocycles. Since these reactions generate a rhodium(I) species after the oxidative annulation, an external or internal oxidant is required to regenerate catalytically active rhodium(III) species. A wide variety of directing groups can be used and these directing groups are incorporated into the annulation products. Although rhodium is very expensive, the use of rhodium complexes as catalysts is advantageous compared to other transition‐metal complexes due to high functional group tolerance and operational simplicity.