Synthesis, molecular structure, and voltammetric behaviour of unusually stable cis-dioxobis(diisobutyldithiocarbamato)tungsten(VI)

The Syntheses and Vibrational Spectra of 16O‐ and 18O‐Enriched cis‐MO2 (M=Mo, W) Complexes

“…Specifically, molecular complexes [MoO 2 (L n )] show two distinctive absorption maxima at 915–935 and 890–905 cm −1 , respectively, whereas complexes [WO 2 (L) n ] display typically two strong vibrational bands at ca . 930–960 and 870–920 cm −1 in their IR spectra ,,,. Generally, these two bands show a difference of 20–35 cm –1 .…”

“…In such reactions, an oxygen atom is transferred from an oxygen donor to a biologically relevant acceptor molecule or vice versa ,,,. Bearing in mind these important biological functions, many examples of tungsten‐ and molybdenum‐containing model compounds for OAT studies have been prepared . We have previously synthesized a number of tungsten VI complexes with amine bisphenolate ligands using tungsten VI alkoxide W(eg) 3 (eg=ethylene glycolate dianion) as a precursor and found that the number of terminal oxido ligands in the formed complex depends on the denticity of the amine bisphenol.…”

Replacement of Molybdenum by Tungsten in a Biomimetic Complex Leads to an Increase in Oxygen Atom Transfer Catalytic Activity

“… 26 − 28 This may mainly be explained by the half-reaction of the catalytic cycle requiring reduction of the metal center ( Scheme 1 a), which is often challenging with tungsten due to its lower redox potential. 29 − 31 Possibly for these reasons, W(V) μ-oxo dimers are only known with scorpionate 32 , 33 and dithiocarbamate ligands, 34 , 35 besides an organometallic example. 36 Comparative studies revealing a higher OAT activity of the tungsten(VI) compound than that of the molybdenum analogue are extremely rare.…”

“…Tungsten­(VI) models in OAT reactions are studied less and mainly alongside analogous molybdenum compounds. Such investigations revealed that analogous Mo­(IV, VI) and W­(IV, VI) complexes are nearly isostructural; however, lower or no catalytic activity of the tungsten system is usually observed. − This may mainly be explained by the half-reaction of the catalytic cycle requiring reduction of the metal center (Scheme a), which is often challenging with tungsten due to its lower redox potential. − Possibly for these reasons, W­(V) μ-oxo dimers are only known with scorpionate , and dithiocarbamate ligands, , besides an organometallic example . Comparative studies revealing a higher OAT activity of the tungsten­(VI) compound than that of the molybdenum analogue are extremely rare.…”

Cis- and trans molybdenum oxo complexes of a prochiral tetradentate aminophenolate ligand: Synthesis, characterization and oxotransfer activity

“…Such molybdopterin-dependent enzymes play key roles in living organisms and are involved in essential steps in the biological sulfur-and nitrogen cycles, where they catalyse oxygen atom transfer (OAT) reactions consisting of the transfer of an oxygen atom to or from a biologically relevant acceptor/donor molecule [16,17]. Thus, a number of dioxomolybdenum(VI) complexes have been studied as models for oxidized forms of molybdenum-containing oxidoreductases that contain Mo(VI)X units (X=O, S) coordinated by at least one dithiolene unit of a molybdopterin [18][19][20][21][22][23][24][25].…”