Synthesis, Structures and Characterization of Dimeric Neutral Dithiolato-Bridged Tungsten Complexes

4 years ago

Synthesis, Structures and Characterization of Dimeric Neutral Dithiolato-Bridged Tungsten Complexes

Bijan Mondal, Babu Varghese, K Bakthavachalam, Sundargopal Ghosh, Ranjit Bag

Novel quadruply-bridged bimetallic dithiolato complexes [(Cp*W)2(µ-S)2(µ,η2-S2CH2)] (3) and an open cage triple-decker complex [(Cp*W)2(µ-S)(µ-η4:η4-B2H2S2)], (2) have been prepared from the treatment of CS2 with an in-situ generated [(Cp*W)2(B2H6)2], (1), obtained from the reaction of [Cp*WCl4] with [LiBH4.thf]. The solid-state X-ray structures of these complexes show the presence of doubly bridging η2-S2B2H2 and η2-S2CH2 ligands with a short W-W bond. While many dimolybdenum-sulfur compounds are known, examples of the tungsten-dithilato complexes are very less and in this view, the isolation of [(Cp*W)2(µ-S)2(µ,η2-S2CH2)] represents a rare example of this type. Electronic structure analysis on the ground of density functional theory (DFT) together with the X-ray diffraction studies rationalised the presence of short W-W and B-B bonds. The large HOMO-LUMO gap has been observed for both the compounds which are consistent with their thermodynamic stability. All the compounds have been characterized by mass spectrometry, 1H, 11B, IR and 13C NMR spectroscopy in solution and the structural architectures were unambiguously established by X-ray crystallographic analysis.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/ejic.201701088