Synthesis of μ-C2S44− Cobalt Complexes by Activation of the 1,3,4,6-tetrathiapentalene-2,5-dione, and Electrochemical Study of [(Cp*Co)2(μ-C2S4)]

Abstract

The bimetallic complex [Cp ( * ) Co) 2 (µ-C 2 S 4 )] in which the two metal centres are linked by an ethylenetetrathiolate C 2 S 4 4− unit, was synthesized in high yield by oxidative addition of 1,3,4,6 tetrathiapentalene-2,5-dione to [Cp ( * ) Co(CO) 2 ]. The X-ray crystal structure of the intermediate product Cp*Co(dmid) (dmid 2− = 4,5-disulfanyl-1,3-dithiol-2-onate) is presented. The electrochemical behaviour of the [(Cp* Co) 2 (µ-C 2 S 4 )] complex was studied in detail in the oxidative range. This study has shown that the nature of the product obtained after oxidation depends on the presence of com-

Isostructural diamagnetic cobalt(III) and paramagnetic nickel(III) dithiolene complexes with an extended benzenedithiolate core [CpMIII(bdtodt)] (M=Co and Ni)

“…A similar behavior was already noticed in [Cp * Co(l-C 2 S 4 )CoCp * ] [26], and attributed to the influence of the kinetics of the acetonitrile coordination following the electron transfer (Scheme 1). Indeed, the similar reduction potential and spectroscopic properties in CH 2 Cl 2 and CH 2 Cl 2 /CH 3 CN indicate that the CH 3 CN coordination does not take place before oxidation.…”

“…The oxidized species of [CpCo(dithiolene)] undergoes a dimerization or a solvent coordination to the metal center. Indeed, [Cp * Co (dddt)] and [Cp * Co(l-C 2 S 4 )CoCp * ] have been reported to dimerize in CH 2 Cl 2 or to react with MeCN after an electrochemical oxidation (EC reaction) [25,26]. In addition, the isoelectronic [(g 6 -arene)Ru II (dithiolene)] complexes can also dimerize by an electrochemical oxidation [27].…”

Regular Acyclic and Macrocyclic [AB] Oligomers by Formation of Push–Pull Chromophores in the Chain‐Growth Step

“…Die vier U‐S‐Bindungen sind mit 2.914(1), 2.946(1), 2.959(1) und 2.984(1) Å länger als in verwandten U IV ‐S‐Dithiolatkomplexen 26. 27 Die zentrale C‐C‐Bindung C55C56 in 2 ist mit 1.498(5) Å die zweitlängste bekannte Bindung dieser Art18–21, 25, 28 und etwas länger als die entsprechende Bindung in [PPh 4 ] 2 [C 2 S 4 ] (1.461 Å) 29. Infolgedessen sind die vier C‐S‐Bindungen mit 1.679(4), 1.671(4), 1.690(4) und 1.687(4) Å deutlich kürzer als für vergleichbare C‐S‐Bindungen berichtet wurde 18.…”

Dinuclear Cp* Cobalt Complexes of the 1,2,4,5-Benzenetetrathiolate Bischelating Ligand

“…In this work, we have investigated a dinuclear cobalt dithiolene complex with the 14-electron π-conjugated btt 4− ligand (Chart ), that is, [Cp*Co(btt)CoCp*] ( 1 ). Most reported cobalt dithiolene complexes are mononuclear complexes, either heteroleptic monodithiolene complexes, such as CpCo(dithiolene), or homoleptic bis(dithiolene) complexes of the general formula [Co(dithiolene) 2 ] n − . – Only a few examples of the dinuclear cobalt dithiolene complex have been reported until recently. Guyon et al have described the dinuclear cobalt dithiolene complexes [CpCo(tto)CoCp] and [Cp*Co(tto)CoCp*], incorporating the 10-electron π-conjugated tto 4− ligand (Chart ) .…”

“…Most reported cobalt dithiolene complexes are mononuclear complexes, either heteroleptic monodithiolene complexes, such as CpCo(dithiolene), or homoleptic bis(dithiolene) complexes of the general formula [Co(dithiolene) 2 ] n − . – Only a few examples of the dinuclear cobalt dithiolene complex have been reported until recently. Guyon et al have described the dinuclear cobalt dithiolene complexes [CpCo(tto)CoCp] and [Cp*Co(tto)CoCp*], incorporating the 10-electron π-conjugated tto 4− ligand (Chart ) . In other dimeric cobalt dithiolene complexes reported by Sugimori et al and formulated as [CpCo(S 2 C 2 (R))] 2 (R = H, Me, SiMe 3 , Ph, p -C 6 H 4 COMe, p -C 6 H 4 NO 2 ), two cobaltadithiolene metallacycles are linked by a single C–C bond (Chart ).…”