Reactivity of CS2 – Syntheses and Structures of Transition-Metal Species with Dithioformate and Methanedithiolate Ligands

Abstract

International audienceThe syntheses and structural characterization of the CS2–metal complexes [(η5-C5Me5M)(η2-S2CH2)(η3-S2CH)] (1: M = Mo; 2: M = W), which feature partially and fully reduced CS2, are reported. In addition, the cis and trans isomers of the dimetallic (sulfido)molybdenum complexes [(η5-C5Me5Mo)2(µ-S2CH2S)2] (3-cis and 4-trans) are described. The [Mo2S4] cores of 3-cis and 4-trans represent paddlewheel-like arrays. All the new compounds were characterized in solution by mass spectrometry, IR spectroscopy, and 1H and 13C NMR spectroscopy. Their structural architectures were established by X-ray crystallographic analysis. Quantum-chemical calculations by DFT methods on the model compounds 1′–4′-trans showed good agreement with the experimentally observed structural parameters. The large HOMO–LUMO (HOMO = highest occupied molecular orbital, LUMO = lowest unoccupied molecular orbital) gaps are consistent with the high thermodynamic stabilities of these complexes. Further, the presence of short metal–metal cross-cluster bonds in the X-ray structures of 3-cis and 4-trans is supported by natural bond order (NBO) calculations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei