Molybdenum trifluoride

Three other binary compounds of molybdenum and fluorine are known to exist molybdenum trifluoride [20193-58-2] MoF, molybdenum tetrafluoride [23412-45-5] MoF, and molybdenum pentafluoride [13819-84-6] MoF. Also known are the two oxyfluorides, molybdenum dioxydifluoride [13824-57-2] M0O2F2, and molybdenum oxytetrafluoride [14459-59-7] MoOF. The use of these other compounds is limited to research appHcations. 

Molybdenum hexafluoride. 3,1412 Molybdenum-iron-sulfur complexes, 4,241 Molybdenum oxide amino acid formation prebiotic systems, 6, 872 Molybdenum storage protein microorganisms, 6, 681 Molybdenum telluride, 3, 1431 Molybdenum tetraalkoxides physical properties, 2, 347 Molybdenum tribromide, 3,1330 Molybdenum trichloride, 3,1330 Molybdenum trifluoride, 3, 1330 Molybdenum trihalides, 3, 1330 bond lengths, 3, 1330 magnetic moments, 3,1330 preparation, 3,1330 properties, 3, 1330 structure, 3,1330 Molybdenum triiodide, 3,1330 Molybdenum trioxide complexes, 3, 1379 Molybdenum triselenide, 3, 143)... 

For molybdenum trifluoride, it has been established that the cubic material contains oxide impurity, and the pure compound has been prepared by the reduction of the pentafluoride (38, 39) or hexafluoride (37) with molybdenum metal and has a rhombohedral unit cell. 

Molybdenum trioxide Chlorine trifluoride, interhalogens, metals... 

The reactivity of fluorine compounds varies from extremely stable, eg, compounds such as sulfur hexafluoride [2551-62 ] nitrogen trifluoride [7783-54-2] and the perfluorocarbons (see Fluorine compounds, organic) to extremely reactive, eg, the halogen fluorides. Another unique property of nonionic metal fluorides is great volatiUty. Volatile compounds such as tungsten hexafluoride [7783-82-6] molybdenum hexafluoride [7783-77-9] ... 

Molybdenum(III) complexes include the molybdenum trihaUdes. Molybdenum trichoride [13478-18-7], trifluoride [20193-58-2], tribromide [13446-57-6], and ttiiodide [14055-75-5] are all known. The oxide dimolybdenum trioxide [1313-29-7], M02O2, and the seldom-studied sulfide analogue [12033-33-9], M02S2, are formally trivalent. 

Chlorine Trifluoride Tech. Bull. , Morristown, Baker Adamson, 1970 Incandescence is caused by contact with bromine, iodine, arsenic, antimony (even at -10°C) powdered molybdenum, niobium, tantalum, titanium, vanadium boron, carbon, phosphorus or sulfur [1], Carbon tetraiodide, chloromethane, benzene or ether ignite or explode on contact, as do organic materials generally. Silicon also ignites [2],... 

Used industrially in the manufacture of fluorocarbons as a chemical intermediate in the manufacture of sulfur hexafluoride, chlorine trifluoride, bromine trifluoride uranium hexafluoride, molybdenum hexafluoride, perchloryl fluoride, and oxygen difluoride and as a rocket propellant. 

Methyl methacrylate 4-Methylnitrobenzene 2- Methylpyridine Methylsodium Molybdenum trioxide Naphthalene 2-Naphthol Air, benzoyl peroxide Sulfuric acid, tetranitromethane Hydrogen peroxide, iron(II) sulfate, sulfuric acid 4-Chloronitrobenzene Chlorine trifluoride, interhalogens, metals Chromium trioxide, dinitrogen pentaoxide Antipyrine, camphor, phenol, iron(III) salts, menthol, oxidizing materials, permanganates, urethane... 

Manganese trichloride oxide, 4141 Manganese trifluoride, 4335 Mercury(II) bromide, 0269 Mercury(I) fluoride, 4312 Mercury(II) iodide, 4602 Molybdenum hexafluoride, 4365 Molybdenum pentachloride, 4180 Neptunium hexafluoride, 4366 Osmium hexafluoride, 4370 Palladium tetrafluoride, 4347 Palladium trifluoride, 4341... 

POTASSIUM CYANIDE POTASSIUM HYDROXIDE LITHIUM HYDRIDE MAGNESIUM OXIDE MANGANESE MOLYBDENUM NITROGEN TRIFLUORIDE AMMONIA... 

Elimination to yield alkenes can be induced thermally or by treatment with acids or bases (for one possible mechanism, see Figure 3.39) [138,206]. Less common thermal demetallations include the thermolysis of arylmethyloxy(phenyl)carbene complexes, which can lead to the formation of aryl-substituted acetophenones [276]. Further, (difluoroboroxy)carbene complexes of molybdenum, which can be prepared by treating molybdenum hexacarbonyl with an organolithium compound and then with boron trifluoride etherate at -60 °C, decompose at room temperature to yield acyl radicals [277]. 

When the chiral molybdenum Ti-allyl-substituted enone 147 was treated with lithium dimethylcuprate, formation of adduct 148 with fair selectivity was observed (Scheme 6.29) [69]. Interestingly, higher selectivities were obtained in the presence of boron trifluoride etherate. It is assumed that Lewis acid coordination induces the s-trans reactive conformation 149 [64]. Consequently, nucleophile attack anti to the molybdenum fragment should afford the major diastereomer 148. 

Compound 388 is an acylating agent for electron-deficient alkenes, in a Michael addition process. It is formed by treating molybdenum hexacarbonyl with an organolithium compound, followed by quenching the intermediate 387 with boron trifluoride (equation 104). The structure of 388 (R = Ph) can be elucidated by NMR spectroscopy. Other examples of enantioselective and diastereoselective Michael-type additions involving lithium-containing intermediates in the presence of chiral additives can be found elsewhere in the literature . 

This simple structure originally was assigned by Gutmann and Jdck 122) to the trifluorides of molybdenum and tantalum and later to NbFa... 

The observations made for the trifluorides of molybdenum, niobium and tantalum let it seem doubtful, whether the compound ZrFs, the formula of which was affirmed by chemical analysis, really crystallizes in a ReOs-type structure, as has been tentatively stated 95). The Zr—F-distance of 1.98 A calculated from the reported lattice constant ( =3.96A) is conspicuously small and would 5ueld a Zrs+ ionic radius of 0.65 A only. Therefore the Zr—F—Zr-chains, linear in the ReOs-type, should rather be angled as in the VF8-t e. 

In the course of a study of the formation of fluorophosphoranes from chloro-phosphines (22) we observed one exception in the compound chloromethyldi-chlorophosphine, which reacted smoothly with antimony trifluoride to give the flammable fluorophosphine, C1CH2PF2, under conditions where many other chloro-phosphines were invariably converted into fluorophosphoranes. As this fluorophosphine is readily available, its interaction with a metal carbonyl derivative was studied, and cycloheptatriene molybdenum tricarbonyl, obtained from the reaction of molybdenum hexacarbonyl with cycloheptatriene (I, 2), was chosen as a starting compound. 

FjO ReSC6, Rhenium(I), pentacarbonyl-(trifluoromethanesulfonato)-, 26 115 FjP, Phosphorus trifluoride, 26 12 F4AuiBOP,C54H45, Gold(l +), p,-oxo-[tris[(triphenylphosphine)-tetrafluoroborate(l -), 26 326 F4B, Borate(l-), tetrafluoro-molybdenum and tungsten complexes, 26 96-105... 

Pentafluorocthyl iodide is of practical interest, particularly as a precursor of higher perfluoroal-kyl iodides. There are several patents for the preparation of the key compound from tetra-fluoroethene, iodine pentafluoride and iodine at 75-80 C in the presence of catalysts anti-mony(III) fluoride, titanium(lV) chloride, boron trifluoride, vanadium(V) fluoride, niobium(V) fluoride, and molybdenum(Vl) fluoride.11-13 The agents iodine monofluoride" and bromine monofluoride" can add to branched pcrfluoroalkcnes, e.g. perfluoro-2-methylbut-2-ene gives perfluoro-2-iodo-2-methylbutane.1415... 

The addition of boron trifluoride as a catalyst has been found to be essential in the fluorination of carboxylic groups of poly(acrylic acid) and poly(methacrylic acid) with sulfur tetrafluoride.12 Boron trifluoride as a Lewis acid is necessary in catalytic amounts to polarize the C = 0 bond before fluorination with molybdenum(VI) hexafluoride takes place.1314... 

Tungsten(VI) fluoride (WF6) and molybdenum(VI) fluoride (MoF6) are available commercially, and can be made by reaction of the metals with fluorine.4 In the case of uranium(VI) fluoride (UF6), a preparation that is claimed5 to be feasible in the laboratory uses uranium metal and chlorine trifluoride uranium(VI) fluoride is prepared6 commercially by the fluorination of uranium(IV) fluoride, itself prepared from an oxide and hydrogen fluoride. 

While arsabenzene does not act as a nucleophile toward hard acids, it does form a-Mo(CO)5 complex 57 on treatment with pyridine-Mo(CO) and boron trifluoride etherate100). Qualitatively complex 57 seems rather weak since on heating it is destroyed, forming small quantities of tc-Mo(CO)3complex 58 101). This rt-complex is more conveniently prepared directly from arsabenzene and Mo(CO)6 or from acid-catalyzed displacement from tris-(pyridine)molybdenum tricarbonyl. 

Similarly, the reaction of phosphorus trifluoride and iron pentacarbonyl 59) at elevated temperatures and pressures results in a mixture of compounds of the general formula Fe(CO)5 B(PF3)B, where n=0-5. All of these compounds were isolated from the reaction mixture by gas chromatography. However, it is stated that equilibrium was most probably not reached and thus no efforts were made to calculate equilibrium constants. Similar studies have been mentioned to be in progress with molybdenum carbonyls (5). 

The detailed structures of many trifluorides were reported by Jack and co-workers, from X-ray powder data, which gave very accurate integrated intensities. Although the results for cubic molybdenum and... 

Phillips and Timms [599] described a less general method. They converted germanium and silicon in alloys into hydrides and further into chlorides by contact with gold trichloride. They performed GC on a column packed with 13% of silicone 702 on Celite with the use of a gas-density balance for detection. Juvet and Fischer [600] developed a special reactor coupled directly to the chromatographic column, in which they fluorinated metals in alloys, carbides, oxides, sulphides and salts. In these samples, they determined quantitatively uranium, sulphur, selenium, technetium, tungsten, molybdenum, rhenium, silicon, boron, osmium, vanadium, iridium and platinum as fluorides. They performed the analysis on a PTFE column packed with 15% of Kel-F oil No. 10 on Chromosorb T. Prior to analysis the column was conditioned with fluorine and chlorine trifluoride in order to remove moisture and reactive organic compounds. The thermal conductivity detector was equipped with nickel-coated filaments resistant to corrosion with metal fluorides. Fig. 5.34 illustrates the analysis of tungsten, rhenium and osmium fluorides by this method. 

The reaction between molybdenum hexacarbonyl and elemental fluorine at —65° results in the formation of Mo2F9, which upon thermal degradation produces molybdenum pentafluoride as one of the products.1 Other syntheses of molybdenum pentafluoride include the reduction of molybdenum hexafluoride with phosphorus trifluoride,2 tungsten hexacarbonyl, or molybdenum metal at high temperatures3 and the oxidation of powdered molybdenum metal with elemental fluorine at 900°.3 The present method consists in the reaction of molybdenum hexafluoride with powdered molybdenum metal at 60° and results in the formation of pure molybdenum pentafluoride in yields of 80% and greater. 

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