The first synthesis of (+)-terreusinone 1, a dipyrrolobenzoquinone with a potent UV-A protecting capability, is described. Key transformations include a one-pot Larock indolization-Sonogashira coupling reaction and the hydroamination of an unsubstituted ortho-alkynylaniline catalyzed by a cationic gold(I) complex. The synthesis proceeds in eight steps from commercially available starting materials, confirming the structure and absolute configuration of the natural product.

The first general synthetic approach to 1,1'-bisindoles is described. Two simultaneous, ambient temperature Mori-Ban reactions were used to effect bisindolization of several diallylated hydrazobenzenes with minimal cleavage of the N-N bond.

An iridium-catalyzed C-H borylation provides the key step in a short synthesis of two indolequinone natural products. This regioselective C-H functionalization strategy delivers 7-borylindoles that undergo facile oxidation-hydrolysis to 7-hydroxyindoles and subsequent oxidation to the desired indolequinones, thereby demonstrating a powerful application of the iridium-catalyzed C-H borylation reaction. A significant result has arisen from the iridium-catalyzed borylation of N-diethylhydrosilyl-6-methoxyindole; even in the presence of a substituent at C6, the N-hydrosilyl group still directs borylation exclusively into the more sterically hindered C7 position in preference to C2.

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A procedure that converts a series of structurally diverse, readily available indole derivatives to their corresponding indolequinones is described. The three-step route commences with an iridium catalyzed C-H borylation to give a 7-borylindole that upon oxidation-hydrolysis affords the 7-hydroxyindole. Subsequent oxidation provides the indolequinone.