Tetrathiomolybdates

The tetrathiomolybdate ion [16550-92-0] (Fig. 2b), which has received great attention in the late 20th century, was first reported by BerzeHus in 1838. The simple preparation from molybdate in basic aqueous solution occurs in high yield according to ... 

The red tetrathiomolybdate ion appears to be a principal participant in the biological Cu—Mo antagonism and is reactive toward other transition-metal ions to produce a wide variety of heteronuclear transition-metal sulfide complexes and clusters (13,14). For example, tetrathiomolybdate serves as a bidentate ligand for Co, forming Co(MoSTetrathiomolybdates and their mixed metal complexes are of interest as catalyst precursors for the hydrotreating of petroleum (qv) (15) and the hydroHquefaction of coal (see Coal conversion processes) (16). The intermediate forms MoOS Mo02S 2> MoO S have also been prepared (17). 

Benzyltriethylammonium tetrathiomolybdate in CH3CN in 61-97% yield. Deprotection is compatible with esters such as benzyl, allyl, acetate, and -butyl esters. ... 

Disulfides can be prepared by treatment of alkyl halides with disulfide ions and also indirectly by the reaction of Bunte salts (see 10-41) with acid solutions of iodide, thiocyanate ion, or thiourea, or by pyrolysis or treatment with hydrogen peroxide. Alkyl halides also give disulfides when refluxed with sulfur and NaOH, and with piperidinium tetrathiotungstate or piperidinium tetrathiomolybdate. ... 

Attempts to electrodeposit M0S2 in a way similar to that used for MoSe2 - in this case from solutions of molybdate and thiosulfate under various conditions of pH and temperature - have been unsuccessful. Instead, thin films of M0S2 were convenienfly deposited from tetrathiomolybdate solutions Ponomarev et al. [149] observed that reduction of MoO in slightly alkaline solutions results in the formation of an X-ray amorphous film which by annealing at 550 in Ar for 1 h... 

Chandra S, Sahu SNJ (1984) Electrodeposited semiconducting molybdenum selenide films. 1. Preparatory technique and stractural characterization. J Phys D Appl Phys 17 2115-2123 Dukstiene N, Kazancev K, Prosicevas 1, Guobiene A (2004) Electrodeposition of Mo-Se thin films from a sulfamatic electrolyte. J SoUd State Electrochem 8 330-336 Ponomarev EA, Neumann-SpaUart M, Hodes G, Levy-Qement C (1996) Electrochemical deposition of M0S2 thin films by reduction of tetrathiomolybdate. Thin SoUd EUms 280 86-89... 

Chlorination of amide or lactam using oxalyl chloride gives the chloro-iminium salts in situ. They react with tetrathiomolybdate to afford the corresponding thioamides and thiolactams in short-time and at low temperature in high yields. This method affords high yields of secondary or tertiary thioamides on the other hand it gives low yield of primary thioamide (17% yield) (Scheme 12).3 3... 

Benzyltriethylammonium tetrathiomolybdate, [BnNEt3]2MoS4, is a useful sulfur transfer reagent which has now been shown to effect a one-pot, three-step sequence of S-transfer— reduction—Michael addition. The intramolecular version successfully produces 1,4-oxathianes from the bromoenone 108 (Scheme 65). In like manner, the bicyclo[3.3.1]nonane skeleton incorporating a thiopyran ring can be constructed . 

Treatment. Since the 1950s, the treatment of Wilson s disease has relied on chelating agents [25]. Early attempts to use BAL or EDTA for this purpose were unsuccessful, but penicillamine, triethylene tetramine dihydrochloride (trientine), and tetrathiomolybdate, all in combination with a low-copper diet, have proved to be effective, and result in the urinary excretion of large amounts of copper. The use of penicillamine is complicated by the fact that it may induce a transient worsening of neurologic function due to rapid mobilization of copper, and also has other side-effects, such as the development of nephrosis. Tetrathiomolybdate is an effective alternative with fewer side-effects [26]. In cases in which the dose was rapidly escalated, however, bone marrow suppression or liver function abnormalities have been described. 

Brewer, G. J., Hedera, P, Kluin, K. J. et al. Treatment of Wilson disease with ammonium tetrathiomolybdate III. Initial therapy in a total of 55 neurologically affected patients and follow-up with zinc therapy. Arch. Neurol. 60 379-385, 2003. 

Mills, C.F., T.T. El-Gallad, I. Breamer, and G. Wenham. 1981. Copper and molybdenum absorption by rats given ammonium tetrathiomolybdate. Jour. Inorg. Biochem. 14 163-175. 

Tetrathiafulvalene (TTF), 23 707 electrochromic material, 6 581, 581t polymers of, 23 708-709 Tetrathiomolybdate ion, 17 22-23 Tetravalent lead, 14 783 Tetravalent manganese compounds,... 

The profitable conversion of thiouronium salts into dialkyl thioethers (see Section 4.1) is less successful for synthesis of diaryl thioethers. For example, l-chloro-4-nitrobenzene reacts with bis-thiouronium salts of the type (H2N)2CS(CH2) SC(NH2)2+ under soliddiquid and liquidrliquid conditions to produce the desired bis-thioethers, ArS(CH2) SAr, (20-35%), together with the diaryl sulphide, Ar2S (5-15%). Higher yields of the diaryl sulphide are observed under liquiddiquid conditions whereas, under solidiliquid conditions, the diaryl disulphide, (ArS)2, (20%) is also formed [56], Diaryl disulphides are the sole products (>65%) from the stoichiometric reaction of aryl diazonium salts with benzyltriethylammonium tetrathiomolybdate [57],... 

An interesting C-S bond formation mediated by benzyltriethylammonium tetrathiomolybdate converts -halo acid chlorides into thiolactones [64] (Scheme 4.16). 

Nitrones and amine A-oxides are deoxygenated by a stoichiometric amount of benzyltriethylammonium tetrathiomolybdate to yield imines and amines, respectively (>80%) [7]. Nitro groups and sulphoxides are not reduced under these reaction conditions. 

Synthetic efforts at preparing model complexes for the FeMo-cofactor have largely focussed on two types of Mo-Fe-S cluster, both of which are prepared via self-assembly reactions using tetrathiomolybdate as starting material. The first of these is the "linear" type of cluster, containing the MoS2Fe unit formed by coordination of discrete MoS - units to Fe. The second is the... 

Characteristics of the coals are summarised in Table I. The reactors were of the tubing bomb type and the initial (cold) hydrogen pressure was 7 MPa. A sulphided Mo catalyst was introduced to the coal by impregnation from an aqueous solution of ammonium tetrathiomolybdate. 

Experiments were carried out to test whether carboxyl groups on a model compound were removed under preliquefaction conditions (350 C, tetrathiomolybdate, naphthalene solvent and nitrogen or hydrogen gas). Results showed that almost all of the carboxyl groups were converted to CO2. This reaction was, however, accompanied by crosslinking. Almost no decarboxylation occurred in the ab nce of the catalyst. 

Illinois 6 coal (1.0 g) was impregnated with ammonium tetrathiomolybdate (0.20 g, 0.77 mmol) in 10 mL of water at 250°C fw 30 minutes. For the mixed metals, 0.385 mmol of metal salt was added. 

The IR and Raman frequencies for the alkali tetrathiomolybdates and -tungstates (156) follow in Table 21. All these compounds crystallize in the jS-K2S04 lattice, space group D2 with Z = 4 having anionic site symmetry C (757). The number... 

Vibrational Spectra of Transition Element Compounds Table 21. Vibrational spectral data (in cm t) for tetrathiomolybdates and -tungstates 756)... 

We therefore needed a ready synthesis of the 1,6-epithio epoxide 119. Normally, for such syntheses, the sulftir atom is introduced at an early stage [64]. However, it appeared to us that a suitable doubly-activated sugar such as 120 should be capable of direct conversion to the 1,6-epithio sugar 121 by treatment with some type of sulfur reagent. Indeed, the o-glucosyl bromide 122 was easily prepared and, upon treatment with either hydrogen sulfide and triethylamine in DMF or benzyltriethylammonium tetrathiomolybdate in chloroform, gave the... 

Tetrathiomolybdate has been prepared with a number of organic cations including NEtf,31 NC4H9 (pyrrolidinium),32,34 N2C4Hfi (piperazinium), NCsHk (piperidinium)34,32 and N4C6H13 (monoprotonated hexamethylene inline).33,32 These salts are useful for structural... 

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