Cobalt fluorides

The ACGIH adopted TLV/TWA for 1992—1993 for fluorides as F is TWA 2.5 mg/m, and for cobalt as Co metal dust TWA 0.05 mg/m. Dust masks should be used while handling both the cobalt fluorides and all other cobalt compounds. CoF is shipped as an oxidizer and a corrosive material. 

Almost all of the biomedical research done in the 25 years following the liquid-breathing work was conducted with commercially available fluorocarbons manufactured for various industnal uses by the electrochemical Simons process (fluonnation in a hydrofluoric acid solution) or the cobalt fluoride process (fluori-nation with this solid in a furnace at about 200 C) These processes tended to yield many by-products, partly because they were, to some extent, free radical reactions and partly because it was difficult to easily achieve complete fluonnation Aromatic hydrocarbons gave better products with the cobalt tnfluonde [73] method, whereas saturated hydrocarbons yielded better products with fluonnation using diluted or cooled gaseous fluorine (Lagow) Incompletely fluormated matenal was either... 

It reacts even more vigorously with most substances than does cobalt fluoride. See other metal halides, silver compounds... 

Formula C0F2 MW 96.93 also forms di- tri- and tetrahydrates. Synonyms cobaltous fluoride cobalt difluoride... 

Hexammino-cobaltic Fluoride, [Co(NH3)6]F3, is also known. It forms yellow prismatic crystals. 

In a somewhat different approach, Asahi Glass KK have claimed [132] that the addition of a transition metal salt (e. g., cobalt-, copper-, lead-, cerium-, bismuth-, manganese-, chromium-, iron- chloride, or cobalt fluoride, etc.) greatly improves the ECF production of perfluorobicyclic compounds, derived from naphthalene, indene, benzofuran, phthalimide, indole, quinolizine, benzotriazole, and quinoline. 

Several chlorofluoropyridines have been fluorinated7 over a mixture of cobalt(III) fluoride and calcium fluoride [it is an open question whether this is just dilute cobalt(III) fluoride or a mixed calcium cobalt fluoride]. The products are mixtures of chlorofluoroazacyclohexenes and -dienes and open-chain 2-azahex-2-enes (compounds 3-6). This is similar to the nonchlorinated pyridines except that 1-methylpyrrolidines are missing. 

It reacts even more vigorously with most substances than does cobalt fluoride. 

The next stage of synthesis was the replacement of pyrrole hydrogen atoms by fluorine atoms. The zinc complex was fluorinated by cobalt fluoride according to the appropriate technique [44, 46], The target product was extracted from reaction products by chromatographic separation in a column filled with neutral aluminum oxide. 

Similar chemistry occurs with R3SnCo(CO)4 if the reaction is performed photochemi-cally in hexane however, when conducted thermally in polar solvents, cobalt fluorides, R3SnF and cobalt cluster compounds are formed342. In the case of an attempted insertion into a Rh—Sn bond under photochemical conditions, ligand exchange chemistry occurred (equation 146)343. 

Hydrated Cobaltous Fluoride, CoF2.2H20, is easily prepared as rose-red crystals by evaporation of a solution of the oxide or carbonate in aqueous hydrogen fluoride. Boiling water decomposes the salt., yielding an insoluble oxy-fluoride of light red colour. 

Cobalt Oxy-fluoride, CoF2.CoO. H20, is obtained by decomposing hydrated cobalt fluoride with boiling water, or by addition of excess of cobalt carbonate to aqueous hydrogen fluoride.5 It is a rose-coloured, crystalline powder. 

Arsenic, antimony, barium, cadmium, chromium, cobalt, fluoride, lead, mercury, molybdenum, nickel, nitrate, selenium, sulfate, uranium (radon may be of concern where there are high uranium concentrations)... 

Cobaltous Fluoride or Cobalt Difluoride, C0F2, mw 96.94, red-rose crysts or powd, mp ca 1200°, bp 1400° sol in cold w hydrofluoric acid decomp in hot w highly toxic irritant. 

Due to the low solubility of cobalt(II) fluoride in most solvents, formation of cobalt fluoro N-donor complexes (which are the only low-valent cobalt fluorides which are reliably reported) features a variety of starting materials. A common theme that runs throughout this work has been the use of [Co(BF4)2] as the fluoride source, and the subsequent controlled decomposition to obtain a metal-bound fluoride. This has been done, for example, with tris- (3,5-dimethyl-pyrazol-l-yl)methyl amine (amtd) to give [M2(amtd)2F(BF4)3(EtOH)Y(H20)] (M = Co, Cu, Zn x = 0-1.5, y = 1-2). The cobalt complex has been structurally characterised by X-ray diffraction [Fig. 3] [57]. Similarly, the combination of [M(BF4)2] (M = Mn, Co, Ni), [M(N03)2], NH4(NCS) and 3,5-diethyl-1,2,4-triazole (detrH) produces... 

Electrochemical fluorination of dialkyl sulphides leads to sulphur(VI) derivatives (see Chapter 2, Section III), and oxidation of sulphur also occurs [246] in cobalt fluoride or direct fluorination reactions (Figure 8.89). 

Cobalt fluoride crystallizes in a closest packed array of fluoride ions with the cobalt ions filling one-half of the octahedral holes. What is the formula of this compound ... 

COBALTOUS CHLORIDE see CNB599 COBALTOUS DIACETATE see CNCOOO COBALTOUS DICHLORIDE see CNB599 COBALTOUS FLUORIDE see CNClOO COBALTOUS MOLYBDATE see CNC250 COBALTOUS NITRATE see CNC500 COBALTOUS OXIDE see CND125 COBALTOUS PERCHLORATE, HEXAHYDRATE see CND900... 

Cobalt fluoride (CbF2) OOiF2(1) 920 Decaborane (B qH ) BigHi4(cr) 310... 

Cobalt fluoride (ObFg) OOjF2(cr,l) 921 Decaborane (B gH ) BigHi4(l) 311... 

Cobalt fluoride (OoFg) OOiF2(g) 922 Decaborane (B gH ) BioHi (cr,l) 312... 

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