Bismuth fluorides

Initial investigations in the Mannich-type reaction of silyl enolates with benzal-dehyde and aniline employed a series of bismuth(III) salts (Scheme 9, Table 10). These results were promising because the corresponding (l-amino ketone could be obtained in moderate to good yield with bismuth halides, except bismuth fluoride (Table 10, entries 1 1). Bismuth nitrate smoothly afforded the expected product (Table 10, entry 5). While bismuth acetate gave no conversion, bismuth trifluor-oacetate provided the product in only moderate yield (Table 10, entries 6 and 7). Phenyl bismuth ditriflate and diphenyl bismuth triflate appeared to be more efficient catalysts than all those previously tested (Table 10, entries 8 and 9). Bismuth(III) triflate led to the expected product in a good yield and in a short reaction time, without any difference between the anhydrous and the hydrated form (Table 10, entries 10 and 11). 

Triorganoantimony and -bismuth fluorides have been prepared by the reaction of the corresponding bromides (or chlorides) with potassium fluoride (equation 229 ). By use of silver fluoride, triorganoantimony bromides have been converted to the corresponding fluorides (equation 230 " ). 

Bismuth fluoride (Bip3) is found in the form of white or gray dimorphic crystals, practically insoluble in water, but soluble in concentrated hydrofluoric acid with the formation of complexes. It volatilizes slowly with partial decomposition at high temperatures. Bismuth bromide (BiBr3) is found as yellowish crystals, soluble in aqueous alkali halides and dilute hydrochloric acid, but practically insoluble in alcohols. It is readily decomposed by water to give bismuth oxybromide BiOBr. Bismuth iodide (BiU) is a black fine crystalline solid with a metallic sheen, practically insoluble in water, but slowly decomposes in hot water. It dissolves in liquid ammonia, aqueous potassium iodide, hydriodic acid and hydrochloric acid, but not so much (ca. 3.5%) in absolute ethanol. When exposed to air for a prolonged time, it is slowly converted to bismuth iodate (Bi(I03)3). Bismuth fluoride of 98% purity costs US 24.30 ( 6200) per 25 g, bromide of 98% purity US 24.90 ( 6200), and iodide of 99% US 34.50 ( 8600). These halides are all corrosive and moisture-sensitive. 

Bismuth fluoride BiFj -61.2 Cesium bromide CsBr -67.2... 

Bismuth (III) telluride Bismuth telluride, undoped. See Bismuth telluride Bismuth ternitrate. See Bismuth nitrate Bismuth trifluoride. See Bismuth fluoride Bismuth trihydrate Bismuth trihydroxide. See Bismuth hydroxide... 

Pearl Super Supreme Pearl Supreme Pearl Supreme UVS Satin B-UVS 7787-60-2 Bismuth chloride 7787-61-3 Bismuth fluoride 7787-64-6 Bismuth iodide 7787-69-1 Cesium bromide 7787-70-4... 

Bervas M, Mansour AN, Yoem W-S, Al-Sharab JF, Badway F, Cosandey F, Klein LC, Amatucci GG (2006) Investigatiem of the hthiation and delithiation conversion meehanisms of bismuth fluoride nanocomposites. J EleeTroehem Soe 153 A799—A808... 

The fluorides of the s- and p-block elements of the periods beyond the second are summarized in Table 7.1. The oxidizing power of fluorine produces numerous examples of hypervalency, in which the maximum valency is shown by the most stable compounds. The only exception to this statement is provided by the bismuth fluorides the hypervalent BiFj (linear polymer) is considerably less stable than the +3 compound. There are a few examples of the inert pair effect, but the fluorides with the group valency are the more stable. 

No Properties Lead Lead —bismuth Fluoride salt Sodium... 

The alkali-metal fluorides and the fluorides of beryllium and zirconium have been given the most serious attention for reactor u.se. Lead and bismuth fluorides, which might otherwise be useful because of their low neutron absorption, have been eliminated because they are readily reduced to the metallic state by structural metals such as iron and chromium. 

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