title: A Metallaanthracene and Derived Metallaanthraquinone.
abstract: Metalla-analogues of archetypal aromatic molecules are attracting ever increasing interest. Although metallabenzenes (which fall within this class) have been well studied, fused-ring metallabenzenes are rare and of the linear polycyclic metallaaromatic hydrocarbons, only metallanaphthalene is known. Herein we report the first metallaanthracene, [Ir(C13H8{CH2CO2Me-5})Cl(PPh3)2]O3SCF3(5), which represents the next member of this series of polycyclic compounds. Structurally, 5 has a number of features in common with anthracene including fused-ring planarity and bond-length alternation. In analogues of classic reactions of anthracene, 5 forms a Diels-Alder adduct with maleic anhydride and on oxidation the unprecedented fused-ring metallaanthraquinone, [Ir(C15H6O{Br-6}{OMe-7}{=O-8}{=O-15})Br(PPh3)2], is obtained.
authors.affiliation: School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Frogley
authors.affiliation: School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: L James
authors.initials: LJ
authors.lastname: Wright
keywords: cyclization; fused-ring metallabenzene; iridium; metallaanthracene; metallacycles