Preparation and oxidation of polarized Au(III) complexes having both the C-deprotonated-2-phenylpyridine (ppy) and a sulfur-rich dithiolate ligand and X-ray crystal structure of [Au(η2-C,N-ppy)-(η2-S, S-C8H4S8}]•0.5DMF

[Au(ppy)(C8H4S8)] [ppy(-) = C-deprotonated-2-phenylpyridine(1-), C8H4S82- = 2-{(4,5-ethylenedithio)-1,3-dithiole-2-ylidene}- 1,3-dithiole-4,5-ditholate(2-)] and [Au(ppy)(C-10-C6S8)] [C-10-C6S82- = 2-{bis(decylthio)-1,3-dithiole-2-ylidene}-1,3-dithiole-4,5-dithiolate(2-)] were prepared. They showed an intense electronic absorption band due to an intramolecular mixed metal/ligand-to-ligand charge transfer transition which is sensitive to a solvent. They exhibit first oxidation potentials of -0.06 to +0.20 V (vs. Ag/Ag+) due to the dithiolate ligand-centered oxidation. They were oxidized by iodine or TCNQ (7,7,8,8-tetracyano-p-quinodimethane) to afford [Au(ppy)(C8H4S8)](I-3) and [Au(ppy)(C-10-C6S8)](I-3) containing the I-3(-) ion, [Au(ppy)(C8H4S8)](TCNQ)(0.6) and [Au(ppy)(C-10-C6S8)](TCNQ)(0.5) containing the TCNQ(.-) radical anion. Their oxidized complexes behave as electrical conductors with electrical conductivities of 2.0 x 10(-2) - 4.0 x 10(-2) S cm(-1) measured for compacted pellets at room temperature. The X-ray crystal structure of [Au(ppy)(C8H4S8)].0.5DMF revealed a two-dimensional array of the molecules with some sulfur-sulfur non-bonded contacts. (C) 2003 Elsevier Science B.V. All rights reserved.