A Channel-Forming Polyiodide Network in [Cu(dafone)3]I12. A Tris Chelate of Dafone and a New Planar Structure for the I122- Ion (Dafone = 4,5-Diazafluoren-9-one)

Treatment of an aqueous solution of copper(II) acetate, dafone, and KI with I 2 in CH 2 Cl 2 leads to the formation of Cu(dafone) 3 I 12 ( 1 ). 1 crystallizes in the orthorhombic system, space group Pbcn, with a = 22.902(4) Å, b = 11.104(2) Å, c = 18.992(7) Å, and Z = 4. Cu(dafone) 3 2+ is the first tris chelate of dafone and is stabilized by a channel-forming network of planar I 12 2 - ions. Temperature dependence of the EPR spectrum indicates fluxionality of the cation.