title: Iridium-catalyzed C-H borylation-based synthesis of natural indolequinones.
abstract: 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.
authors.affiliation: School of Chemical Sciences, University of Auckland, 23 Symonds Street, Auckland, New Zealand.
authors.forename: Christy
authors.initials: C
authors.lastname: Wang
authors.forename: Jonathan
authors.initials: J
authors.lastname: Sperry
mesh_terms: D002384:Catalysis; D006860:Hydrogen Bonding; D045563:Indolequinones / Q000138:chemical synthesis* / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction
chemical_list: D045563:Indolequinones; D007211:Indoles; D007495:Iridium