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Nickel trifluoride reactions

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. [Pg.186]

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). [Pg.214]

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... [Pg.30]

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. [Pg.21]

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. [Pg.223]

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). [Pg.199]

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). [Pg.156]

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... [Pg.157]

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... [Pg.631]

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... [Pg.281]

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... [Pg.371]

Bis(l,5-cyclooctadiene)nickel(0), 35 By Diels-Alder reaction Boron trifluoride etherate, 43... [Pg.395]

C (190-196) and by the thermal decomposition of the trifluoride at 800°C in air (191, 197, 198). The lanthanum compound itself may also be prepared by hydrolysis of the trifluoride (199) and by the reaction of the oxide with molten sodium fluoride (200). On treatment with CFCI3 (201), it is converted back to the trifluoride. The cerium analog has been prepared from Ce02 by reaction with CeF3 at 2750°C (202) or with CeF3 and cerium metal at 900°C in a nickel tube (203). The infrared spectra of these solids have been reported (204). [Pg.86]

Vigorous exothermic reaction with benzene + Raney nickel catalyst metals (e.g., lithium calcium barium strontium sodium potassium above 300°C) palladium(II) oxide palladium trifluoride l,l,l-tris(hydroxymethyl)nitromethane + nickel catalyst. [Pg.742]

Chlorine trifluoride (0.18 l./minute) and chlorine (0.22 l./minute) are mixed together at a T-junction and passed through the first nickel tube, which is maintained at 350°. The gases emerging from this tube are mixed with sulfur(IV) fluoride (0.54 l./minute) and passed into the second reactor, the optimum temperature for which is 375°. Lower temperatures result in incomplete conversion higher temperatures cause the following side reaction to become increasingly important ... [Pg.162]

Recently, Kruck (118) succeeded in preparing Ni(PF3)4 from metallic nickel and phosphorus trifluoride under drastic conditions (350 atm., 100°C.), as did Street and Burg under mild conditions (181), even though Wilkinson and Chatt (52, 202) had previously reported that no reaction occurs between these reagents. [Pg.324]

Furthermore, a vast number of organometallic catalyzed reactions can be performed in a biphasic manner thus proving that also uncommon reactions may be worth to be investigated in liquid/liquid systems. For instance, Braddock describes the atom economic nitration of aromatics in a two-phase process [192], Nitration of aromatics leads usually to excessive acid waste streams and the classical Lewis acid catalysts such as boron trifluoride are destroyed in the aqueous quench after the reaction thus making any recycle impossible. In the method of Braddock the ytterbium triflate catalyst is solved in the aqueous phase and can be recycled by a simple evaporative process. Monflier and Mortreux [193] investigated the nickel catalyzed isomerization of olefins, for instance allylbenzene, in a two phase system yielding good yields of cis- and trans-methylstyrene. [Pg.237]


See other pages where Nickel trifluoride reactions is mentioned: [Pg.224]    [Pg.523]    [Pg.21]    [Pg.198]    [Pg.176]    [Pg.154]    [Pg.160]    [Pg.161]    [Pg.161]    [Pg.285]    [Pg.445]    [Pg.184]    [Pg.185]    [Pg.145]    [Pg.171]    [Pg.1265]    [Pg.134]    [Pg.742]    [Pg.393]    [Pg.163]    [Pg.313]    [Pg.184]    [Pg.185]    [Pg.24]    [Pg.294]    [Pg.247]    [Pg.562]   
See also in sourсe #XX -- [ Pg.843 ]




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