Crystal structure of Tl5{[Nb2S4Br8]Br}

Dinuclear Vanadium Sulfide Clusters: Synthesis, Redox Behavior, and Magnetic Properties

“…These clusters are easily available and rather stable in the case of molybdenum. For vanadium, dinuclear {V 2 (µ‐S 2 ) 2 } 4+ (briefly {V 2 S 4 } 4+ ) complexes are most common among vanadium sulfide clusters; they are the closest relatives of dinuclear niobium complexes , . These clusters exist in dithiocarbamate and xanthate complexes [V IV 2 (S 2 ) 2 (RCS 2 ) 4 ] (R = Et 2 N, cyclo ‐C 4 H 8 N, n ‐Bu 2 N, EtO, i PrO and others).…”

AlNbBr8 – Preparation, Crystal Structure, and Vapor Pressure Studies

“…In this case, a halometalate ionic liquid forms,26 which can act as source of [AlBr 4 ] – and can serve as ligands for the {Nb 2 (S 2 ) 2 } 4+ units. In our particular case, the formation of [Nb 2 (S 2 ) 2 (AlBr 4 ) 4 ] was expected by excision reaction similarly to reaction of NbS 2 Br 2 with KNCS melt giving [Nb 2 (S 2 ) 2 (NCS) 4 ] 4– 27 or with TlBr with the formation of Tl 5 [Nb 2 (S 2 ) 2 Br 8 ]Br 28. However, NbS 2 Br 2 did not dissolve in ionic liquid, and obviously underwent decomposition under more drastic conditions, employed to enhance its reactivity, that resulted in sulfur loss and Nb IV to Nb V oxidation (perhaps by internal redox reaction between Nb IV and S 2 2– yielding Nb V and S 2– ), which was replaced by Br – in the coordination sphere of Nb with the formation of 1 .…”

Thioxanthate complexes of {Nb2S4}4+

“…Thus, halide and pseudohalide complexes [Nb 2 S 4 X 8 ] 4À (X = Br, Cl, NCS) are known, as well as complexes [Nb 2 S 4 (LL) 4 ] with bidentate ligands like oxalate, b-diketonate, dithiophosphate, dithiocarbamate and xanthate. Even a hydrolytically stable aqua-complex [Nb 2 S 4 (H 2 O) 8 ] 4+ has been reported [1][2][3][4][5][6]. According to theoretical calculations, the {Nb 2 (l 2 -S 2 ) 2 } 4+ core may be interesting as a catalytic agent in hydrogenation, alkene and alkyne activation or hydrodesulfurization [7].…”