Structural and electronic analysis of bimetallic thiolate complexes of group-5 transition metal ions

The chemistry of group-5 transition metals, namely vanadium, niobium, and tantalum supported by thiolate ligand framework, has been described. Special emphasis given to the electronic structural properties binuclear complexes metals exhibiting interesting coordination modes chelating ligands. mild thermolysis [(CH2S2)4B]Na5 with [Cp*VCl2]3 afforded divanadium trithiocarbonate complex, [(Cp*V)2(μ-CS3-κ2S,S')(μ-H2CS2-κ2S'',S''')] (1) along [{S(CH2S)2}VOCp*] (2). single crystal X-ray structure 1 illustrates that methanedithiolate ligands are symmetrically coordinated two {Cp*V} units. However, reaction heavier metal precursor, [Cp*NbCl4] at 60 °C in toluene produced a bimetallic trithiolate complex [(Cp*Nb)2(μ-SCS2-κ1S:κ3C,S',S'')(μ-S)2] (3) [(Cp*Nb)2(μ,η2:η2-SH3B)(μ-S)(μ-H2CS2-κ2S,S')]. In similar manner, [Cp*TaCl4] led formation ditantalum [(Cp*Ta)2(μ-S)(μ-S2CH2CHS2-κ2S:κ2S',S'')(μ-H)(μ-S2CH2-κ2S''',S'''')] (4) [Cl(Cp*Ta)2(μ-H)(μ-S2CH2-κ2S,S')(μ-S)(μ-S2CH2-κ2S'':κ1S''')] (5) [(Cp*Ta)2(μ-S){μ-(BH2S)(CH2S)2(BS3)-κ2B:κ2S:κ4S',S'',S''',S''''}]. LiBH4·THF followed presence S2C·PPh3 [(Cp*Ta)2(μ-S)(μ-S2CH2-κ2S,S')(μ-H)(μ-CHS3-κ2S'':κ2S''',S'''')] (6) [(Cp*Ta)2(μ-S2CH2-κ2S,S')2(μ-H)(μ,η2:η2-B2H5)] (I) [(Cp*Ta)2(μ,η2:η2-B2H6)2] (II). Complex 3 is an example {CS3} stabilized niobium complex. (dimercaptomethyl)-methanedithiolate (C2H3S4) 4 both centres via three sulfur donors displayed exclusive bonding mode (μ,κ2S:κ2S',S''). 5 consists (S2CH2) different towards centres, whereas methanetrithiolate (HCS3) units 6. This study demonstrates these vary depending on reflected paramagnetic behaviour vanadium 1. contrast, 3, 4, 6 diamagnetic. Further, theoretical investigations provided insights into structures complexes.