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Flourine

At 225—275°C, bromination of the vapor yields bromochloromethanes CCl Br, CCl2Br2, and CClBr. Chloroform reacts with aluminum bromide to form bromoform, CHBr. Chloroform cannot be direcdy fluorinated with elementary flourine fluoroform, CHF, is produced from chloroform by reaction with hydrogen fluoride in the presence of a metallic fluoride catalyst (8). It is also a coproduct of monochlorodifluoromethane from the HF—CHCl reaction over antimony chlorofluoride. Iodine gives a characteristic purple solution in chloroform but does not react even at the boiling point. Iodoform, CHI, may be produced from chloroform by reaction with ethyl iodide in the presence of aluminum chloride however, this is not the route normally used for its preparation. [Pg.524]

Poison A gas explosives-A/B, organic peroxide, flammable solid, materials dangerous when wet, chlorine, flourine, anhydrous ammonia, radioactive materials, NFPA 3 4 for any categories including SF>ecial hazards. PCB s fire, DOT inhalation hazzird, EPA extremely hazardous substances, and cryogenics. [Pg.13]

Tantalum is severely attacked at ambient temperatures and up to about 100°C in aqueous atmospheric environments in the presence of fluorine and hydrofluoric acids. Flourine, hydrofluoric acid and fluoride salt solutions represent typical aggressive environments in which tantalum corrodes at ambient temperatures. Under exposure to these environments the protective TajOj oxide film is attacked and the metal is transformed from a passive to an active state. The corrosion mechanism of tantalum in these environments is mainly based on dissolution reactions to give fluoro complexes. The composition depends markedly on the conditions. The existence of oxidizing agents such as sulphur trioxide or peroxides in aqueous fluoride environments enhance the corrosion rate of tantalum owing to rapid formation of oxofluoro complexes. [Pg.894]

Halogens Although tantalum is severely attacked by flourine at room temperature it does not react with liquid chlorine, bromine and iodine up to 150°C and the metal suffers no appreciable attack in wet or dry bromine, chlorine and iodine below 250°C. It is virtually uncorroded by hydrogen bromide and hydrogen chloride below 370°C, attack starting at about 375 and 410°C respectively. [Pg.898]

Acetylene Chlorine, bromine, copper, silver, flourine or mercury... [Pg.158]

Acetone Acetylene Alkali and alkaline earth metals, e.g. sodium, potassium, lithium, magnesium, calcium, powdered aluminium Anhydrous ammonia Concentrated nitric and sulphuric acid mixtures Chlorine, bromine, copper, silver, flourine or mercury Carbon dioxide, carbon tetrachloride, or other chlorinated hydrocarbons. (Also prohibit, water, foam and dry chemical on fires involving these metals - dry sand should be available.) Mercury, chlorine, calcium hypochlorite, iodine, bromine or hydrogen fluoride... [Pg.165]

Acke DRJ, Orru RVA, Stevens CV (2006) Continuous synthesis of tri- and tetra-substituted imidazoles via a multicomponent reaction under microreactor conditions. QSAR Comb Sci 25 474-483 Antes J, Tuercke T, Marioth E, Lechner F, Scholz M, Schntirer F, Krause HH, Lobbecke S (2001) In Matlosz M, Ehrfeld W, Baselt JP (eds) IMRET 5 Proceedings of the Fifth International Conference on Microreaction Technology. Springer Berlin New York Heidelberg, pp 446 153 Barrow D, Cefai J, Taylor S (1999) Shrinking to fit. Chem Ind 15 591-594 Bradley D (1999) Chemical Reduction. Eur Chem 1 17-20 Chambers RD, Spink RCH (1999) Microreactors for Elemental Flourine. Chem Comm 10 883-884... [Pg.16]

Boron Carbon Nitrogen Oxygen Flourine Neon... [Pg.343]

When the anodic fluorination of 2-monofluoroethyl sulfide 5 is carried out in methanol containing Et3N-3HF instead of acetonitrile as a solvent, interestingly the a-methoxylated product 7 rather than the a-flourinated product 6 is obtained exclusively (Scheme 6.10) [51]. As described above, 7 is not obtained from 5 under conventional anodic methoxylation conditions. Therefore, that this novel fluoride ion promoted anodic methoxylation is remarkable. As shown... [Pg.33]

The a-methoxylated products are highly useful building blocks for the construction of a carbon-carbon bond a to the trifluoromethyl and diflu-oromethyl groups, which is difficult to obtain by other methods, as shown in Scheme 6.15. Thus, a-tri and a-difluoromethylated a-aminonitriles, which are precursors to the corresponding fluorinated a-amino acids, have been prepared in good yields, and flourinated homoallyanilines have been also successfully prepared [44]. in addition, tri- and difluoromethylated tetra- and dihydroquinoline derivatives can be prepared by cationic polar cycloaddition in high yields [45]. [Pg.39]

When vinyl flouride is polymerized, a certain percentage of the flourine atoms are found on adjacent carbon atoms. When polyvinyl alcohol made by hydrolyzing polyvinyl acetate was treated with periodic acid by Flory, he found that the molecular weight was greatly reduced, indicating that there were 1,2-glycol units in the chain. But most of the polymers were regular head-to-tail polymers. [Pg.58]

Use of Original Flourinated Telomers in the Synthesis of Hybrid Sihcones... [Pg.77]

Both molecules contain polcir covalent bonds based on electronegativity difference between the atoms. The C-F bonds of CF are slightly more polar than the H-0 bonds of water due to the greater difference in electronegativity between Ccirbon and flourine (1.5 versus 1.4), but the bonds are very close to being the same. [Pg.80]

For reviews of flourinaled carbenes, see Seyferth in Moss Jones Carbenes, vol. 2 Wiley New York, 1975. pp. 101-158 Sheppard Sharis Organic Fluorine Chemistry W. A. Benjamin New York, 1969, pp. 237-270. Dolbier Burkholder Tetrahedron Lett. 1988, 29, 6749. [Pg.867]


See other pages where Flourine is mentioned: [Pg.217]    [Pg.226]    [Pg.54]    [Pg.514]    [Pg.350]    [Pg.497]    [Pg.504]    [Pg.18]    [Pg.667]    [Pg.896]    [Pg.525]    [Pg.1165]    [Pg.346]    [Pg.586]    [Pg.353]    [Pg.721]    [Pg.403]    [Pg.84]    [Pg.175]    [Pg.248]    [Pg.80]    [Pg.248]    [Pg.29]    [Pg.170]    [Pg.362]    [Pg.151]    [Pg.181]    [Pg.1299]    [Pg.18]    [Pg.174]    [Pg.64]    [Pg.616]    [Pg.367]    [Pg.151]   
See also in sourсe #XX -- [ Pg.149 ]




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Flourine atomic

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