From Nitrogen Trifluoride

N2F4 was first prepared by thermal reaction of NF3 with various fluoride acceptors such as Cu, As, Sb, Bi, or stainless steel [1, 2]. Thus, N2F4 was produced in 62 to 71% yield based on NF3 consumed (42 to 62% conversion) in a Cu-packed flow reactor at 375°C with a residence time of 13 min [1,2]. Oxygen or nitrogen oxides are added to the NF3 to reduce the induction period of the reaction and residence time in the Cu-packed reactor [3]. Although Cu is the most effective in producing N2F4 the reaction is erratic and often leads to complete reduction of NF3 to 

N2F4 besides cis- and trans-N2F2, N2, and F2 were identified after exposure of NF3 to large doses of 3-MeV bremsstrahlung at 77 K [13]. The radiation-chemical yield G for the formation of N2F4 by °Co y-irradiation (dosage up to 50 Mrad, dose rate 7.1 Mrad/h) of NF3 at 77 K was determined to be 0.4 to 0.5 molecule/100 eV in the absence of fluorine acceptors [14]. G(N2F4) = 0.1 molecule/100 eV was found on irradiation of a liquid NF3 layer of about 5 mm thickness with 800-keV electrons at 77 K (absorbed dose 1600 Mrad) [16]. 

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Difluorodiazene contaminated with SiF4 and NF3 is held at —195°C. This mixture is passed through a sodium fluoride trap to remove SiF4 by the formation of Na2SiF6. Difluorodiazene may be separated from nitrogen trifluoride by gas chromatography with the use of a 25-ft. X 0.25-in. aluminum or copper column... 

Jhe remarkable stability of the difluoramino radical which has recently been established quantitatively (8,14) was presaged by its early chemistry. In retrospect it is apparent that the formation of tetrafluorohydrazine from nitrogen trifluoride under hot tube conditions (4) involved the formation of the difluoramino radical, from which it is more diflScult to remove another fluorine than from nitrogen trifluoride. At the time of the original synthesis, however, it could only be marveled at that N2F4, a compound much closer to nitrogen than NF3, would survive conditions that decomposed the latter. 

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] ... 

E. H. Vemot and C. C. Haun,M< / Toxicology and Proposed Emergemy Exposure Eimits of Nitrogen Trifluoride, AMRL-TR-69-130-Paper No. 13 (AD 710062), Contract E33615-70-V-1046, Syste-Med Corp., Dayton, Ohio, Dec. 1969. Reprinted from the Proceedings of the 5th Annual Conference on Atmospheric Contamination in ConhnedSpaces, Sept. 16—18, 1969, AMRL-TR-69-130 (AD 709994), Dayton, Ohio, Dec. 1969, pp. 165—171. 

The products of the electrochemical perfluorination of aromatic and heteroaromatic compounds are the corresponding perfluorinated cyclic and heterocyclic alkanes.28 and also per-fluorinated derivatives of the heteroaromatic compounds. Perfluorocyclohexane is the principal product from the electrochemical fluorination of benzene and fluorobenzene. Chloro derivatives of perfluorocyclohexane are produced from chlorobenzenes. Anisoles give fully saturated per-fluoro ethers, together with cleavage products. Extensive cleavage is observed in the fluorination of benzenethiols. Chloropyridines, fluorocarbons and sulfur hexafluoride or nitrogen trifluoride are characteristic byproducts from the above scries of reactions. 

Massone, J. Separation of nitrogen trifluoride from carbon tetrafluoride by gas chromatography on poropakQ. Analysis of nitrogen trifluoride. Z. Anal. Chem. 235, 341 (1968). 

Nitrogen trifluoride and tetrafluorohydrazine were obtained from Peninsular ChemResearch, Inc., and Air Products Inc., respectively. Difluorodiazine was prepared by the reaction of N2F4 with A1C13 at -78° C. (9). 

Now, what kind of dipole moment would we expect for nitrogen trifluoride, NF3, which, like ammonia, is pyramidal Fluorine is the most electronegative element of all and should certainly pull electrons strongly from nitrogen the N—F bonds should be highly polar, and their vector sum should be large—far larger than for ammonia with its modestly polar N—H bonds. 

Amine-boranes are important boron-nitrogen compounds. They are prepared by various methods such as direct combination of amine and diborane,1,2 reaction of tetrahydroborates with ammonium salts,3 transamination of amine-boranes,4 or displacement of tetrahydrofuran from tetrahydrofuran-borane which is first prepared from boron trifluoride etherate and sodium tetrahydroborate,5 or by less convenient methods like reduction of an appropriate... 

Cleavage of Benzyl Carbamates. The removal of the benzy-loxycarbonyl (Cbz) group from nitrogen can be achieved successfully using boron trifluoride etherate in the presence of either a thiol or dimethyl sulfide. The carbamates derived from secondary amines are cleaved more rapidly than those from primary amines using the ethanethiol method, even when using BF3-OEt2 as the solvent. The procedure allows reasonable selectivity, as shown in eq 11. ... 

The flame reactions of alkali metal vapors (Li, Na, Cs) with nitrogen trifluoride between about 500 and 1000 K and at a few Torr show strong chemiluminescence. The emission results from electronically excited alkali metal atoms. Photon yields of up to 3% were measured. The excitation mechanism was assumed to involve the formation of an excited species and the transfer of energy from this species to the alkali metal atom (A) according to the simplified sequence [1,2] A +NF,->AF(v) +NF,, ... 

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