Spectroscopic and electrical properties of the [W(C3Se5)3] anion complex (C3Se5 = 1,3-diselenole-2-selone-4,5-diselenolate) and the oxidized species

NBuⁿ₄]₂W(C₃Se₅)₃] (C₃Se₅^2? = 1,3-diselenole-2-selone-4,5- diselenolate(2?)) was prepared by the reaction of Na₂C₃Se₅] with WCl₆ in ethanol, followed by addition of NBuⁿ₄]Br. The cyclic voltammogram in dichloromethane exhibits two oxidation peaks at ?0.04 and +0.03 V (versus SCE). The complex reacted with Fe(C₅Me₅)₂]BF₄], iodine or TTF]₃BF₄]₂ (TTF^·+ = the tetrathiafulvalenium radical cation) in acetonitrile to afford the oxidized complexes Fe(C₅Me₅)₂]_0.5W(C₃Se₅)₃], NBuⁿ₄]_0.1W(C₃Se₅)₃] and TTF]_0.5W(C₃Se₅)₃], respectively. Current-controlled electrochemical oxidation of the complex in acetonitrile gave NBuⁿ₄]_0.6W(C₃Se₅)₃]. The oxidized complexes exhibit electrical conductivities of 4.7×10 ^?5?1.5×10^?3 S cm^?1 at room temperature measured for compacted pellets. Electronic absorption, IR and ESR spectra of these complexes are discussed.