Nickel trifluoride

Nickel Trifluoride Syntheses. As a dry solid, NiFa decomposed to produce a dark brown (nearly black) material which gave an X-ray powder diffraction pattern which showed it to have a rhombohedral variant of the pyrochlore structure (see below and Table 1) ... 

Chlorine Trifluoride. Chlorine trifluoride is produced commercially by the continuous gas-phase reaction of fluorine and chlorine ia a nickel reactor at ca 290°C. The ratio of fluorine to chlorine is maintained slightly in excess of 3 1 to promote conversion of the chlorine monofluoride to chlorine trifluoride. Sufficient time ia the reactor must be provided to maintain high conversions to chlorine trifluoride. Temperature control is also critical because the equiHbrium shift of chlorine trifluoride to chlorine monofluoride and fluorine is significant at elevated temperatures. 

K [14881-07-3], Rb [72151 -96-3], and Cs [72138-72-8]), are prepared by reaction of elemental fluorine, chlorine trifluoride, or xenon difluoride and a mixture of nickel fluoride and alkaH metal fluorides or other metal haHdes (16,17). If the fluorination is carried out using mixed fluorides, a lower temperature can be used, yields are quantitative, and the final products are of high purity. Bis(tetrafluoroammonium) hexafluoronickelate [6310540-8], (NE 2N iF6> prepared from Cs2NiF3 and NE SbE by a metathesis in anhydrous HE, is also known (18). 

The time-weighted, 8-h average limit for exposure to bromine pentafluoride is 0.1 ppm (67). Materials of constmction suitable for use with the bromine fluorides include nickel. Monel metal, or Teflon. For shipping, bromine trifluoride and pentafluoride are classified as oxidizers under DOT regulations. The trifluoride also requires a poison label. 

Phosphorus pentafluoride Phosphorus trifluoride F T Steel, nickel, Monel and Pyrex for dry gas. For moist gas hard rubber and paraffin wax Steel, nickel, Monel and the more noble metals and Pyrex for dry gas... 

Examples of template procedures in which the ring-closing condensation involves reaction at a centre other than a donor atom have been documented. In an early synthesis of this type, the reaction of bis-(dimethylglyoximato)nickel(n) (62) with boron trifluoride was demonstrated to yield the corresponding complex of the N4-donor macrocycle (63) (Schrauzer, 1962 Umland Thierig, 1962). In this reaction the proton of each bridging oxime linkage is replaced by a BF2+ moiety. X-ray... 

Nickel carbonyl Niobium Nitrates Air, bromine, oxidizing materials Bromine trifluoride, chlorine, fluorine Aluminum, BP, cyanides, esters, phosphorus, tin(II) chloride, sodium hypophos-... 

For the more vigorous reactions, a twin-cell calorimeter was devised (188). It consisted of two nickel cylinders connected by a stainless steel needle valve and tubing and held rigidly to a metal top-plate. The cylinders and connections were immersed in a wide-necked Dewar vessel containing carbon tetrachloride which would react mildly with any BrF3 that escaped. Bromine trifluoride contained in one cylinder was transferred to the solid contained in the other cylinder by opening the valve and applying controlled suction. All measurements were made externally on probes in the carbon tetrachloride. 

The use of additional substances to increase the activity of a catalyst is a well known phenomenon. Hydrogen chloride or traces of water are known to promote aluminum chloride catalyzed reactions. In the same way the reaction of isoparaffins with olefins has been shown to be catalyzed by boron trifluoride in the presence of nickel powder and with water as the promoter (Ipatieff and Grosse, 76). Hydrogen fluoride can take the place of the water and thus serve as the promoter. 

Pyridine is converted into perfluoropiperidine (82) in low yield by reaction with fluorine in the presence of cobalt trifluoride (50JCS1966) quinoline affords (83) under similar conditions (56JCS783). Perfluoropiperidine can be obtained electrochemically. This is useful, as it may be readily aromatized to perfluoropyridine by passing it over iron or nickel at ca. 600 °C (74HC(14-S2)407). Recently, pyridine has been treated with xenon difluoride to yield 2-fluoropyridine (35%), 3-fluoropyridine (20%) and 2,6-difluoropyridine (11%), but it is not likely that this is simply an electrophilic substitution reaction (76MI20500). 

Dimethylcyclopropene undergoes efficient cyclodimerization giving 3 (R1 = R2 = Me) in the presence of palladium(O), nickel(O) complexes16,17 or Lewis acids such as boron trifluoride and aluminum trichloride-diethyl ether complexes.16... 

Organic derivatives of phosphorus trichloride—i.e., chlorophosphines of the types RPC12 or R2PC1—had never been fluorinated. We assumed the hitherto unknown fluorophosphines to be possibly interesting ligands in coordination chemistry. Such expectations were supported by earlier observations of Chatt (5, 6) and Wilkinson (32), who found that the parent compound phosphorus trifluoride as a ligand in certain coordination compounds with platinum or nickel behaved very much like carbon monoxide. 

Knowing all these facts, especially the difficult access to fluorophosphines and the poor donating abilities of phosphorus trifluoride (5, 6), we decided to use another approach, which readily led to a number of coordination compounds with fluorophosphine ligands—namely, the fluorination of chlorophosphines already coordinated to the transition metal, where the 3s electrons of phosphorus are blocked by the complex formation. There was no reaction between elemental nickel and phosphorus trifluoride, even under extreme conditions, whereas the exchange of carbon monoxide in nickel carbonyl upon interaction with phosphorus trifluoride proceeded very slowly and even after 100 hours interaction did not lead to a well defined product (5,6). 

In our study of the fluorination of coordinated chlorophosphine ligands (23), we started out with tetrakis(trichlorophosphine)nickel-(0), which could previously be converted into tetrakis(trifluorophosphine)nickel-(0) by displacement of the coordinated phosphorus trichloride with excess phosphorus trifluoride in a sealed tube (32). The limitations of this method, requiring the use of phosphorus trifluoride, a low boiling gas, under pressure, and involving the mechanical separation of the fluorophosphine complex from phosphorus trichloride, are obvious, and the yield was low. A straightforward method for the synthesis of this interesting compound was found in the fluorination of the coordinated phosphorus trichloride with potassium fluorosulfinate ... 

Tetrakis(phenyldifluorophosphine)nickel-(0) could also be obtained, using arsenic trifluoride in the presence of catalytic amounts of antimony pentachloride, or zinc fluoride as fluorinating agents. Yields as high as 50% could be obtained, but sizable decomposition on the process of fluorination of the chlorophosphine nickel-(0) complexes in solution could not be entirely suppressed. The marked instability of zerovalent nickel-phosphine complexes in solution in organic solvents, even under strictly anhydrous and anaerobic conditions, has been noted by several workers (16,20), but is still lacking a detailed explanation. A closer examination of the system carbon tetrachloride-tetrakis(trichlorophosphine)nickel-(0) (23) showed the main pa h of the reaction to consist in the formation of hexachloro-ethane with conversion of zerovalent into bivalent nickel, while the coordinated... 

In addition to fluorine itself, fluorine compounds have also been recommended. Chlorine trifluoride (C1F3) with a boiling point of 12°C and a density of 1.77 g/cm3 is the most promising for use in rocket propulsion. Its specific gravity is 1.85, heat of formation —AH =41.0 kcal/mole. It is obtainable by the action of fluorine on chlorine in an atmosphere of nitrogen at 280°C, in a reactor of copper or nickel. 

Bromofluoromenthane has been prepared in high yield using a one-step reaction with bromine, hydrogen fluoride and methane in the presence of an aluminum trifluoride fluidized bed or fluorinated aluminum catalysts optionally containing cobalt or nickel between 450 and 500°C.20... 

In addition to the traditional catalysts aluminum trifluoride, chromium oxyfiuoride and iron(III) fluoride, published references to chlorofluorocarbon disproportionation reactions describe zinc aluminate (ZnAl,04)l> and nickel(II) chloride on "/-aluminum oxide as carriers.20... 

Dichloro-2,2-difluoroethylene, 105 (Diethylamino)sulfur trifluoride, 110 Reduction reactions (see also Deoxygenation, Reductive. . . ) of acetals and ketals Dibromoalane, 237 Diisobutylaluminum hydride, 237 Triethylsilane-Tin(IV) chloride, 237 of acetates and other esters to alkanes Nickel boride, 197 Triphenylsilane, 334 of acyl halides to alcohols Sodium cyanoborohydride-Tin(II) chloride, 280... 

Diphenylphosphine)lithium, 126 Nickel boride, 197 Samarium(II) iodide, 270 to 1,2-disubstituted compounds B-3-Pinanyl-9-borabicyclo-[3.3.1]nonane, 249 Titanium(III) chloride, 302 of phosphorus compounds Lithium aluminum hydride-Cerium(III) chloride, 159 of sulfoxides and sulfones Sodium iodide-Boron trifluoride ether-ate, 282... 

Bis(l,5-cyclooctadiene)nickel(0), 35 By Diels-Alder reaction Boron trifluoride etherate, 43... 

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