Bromic acids

CH3C(0)CH2Br. Colourless liquid which rapidly becomes violet in colour it is a powerful lachrymator b.p. 1367725 mm. Manufactured by treating aqueous propanone with bromine at 30-40 C it is usual to add sodium chlorate(V) to convert the hydro-bromic acid formed by the reaction back to bromine. It is not very stable and decomposes on standing. 

In the dark, hypobromous acid decomposes to bromic acid and bromine. Bromic acid is relatively unstable and decomposes slowly to give bromine and oxygen. 

Acetophenone.—The Fnedel-Crafts reaction, of which this pieparation is a type, consists in the use of anhydious aluminium chlonde for effecting combination between an aromatic hydrocarbon or its deiivative on the one hand, and a halogen i,Cl 01 Bi) compound on the othei. The leaction 13 always accompanied by the evolution of hydiochloiic or hydio-bromic acid, and the product is a compound with AlCl-j, which decomposes and yields the new substance on the addition of watei. This reaction has been utilised, as in the present case, (r) for the prepaiation of ketones, in which an acid chloiide (aliphatic or aromatic) is employed,... 

Protonation with strong acids such as hydrochloric acid and hydro-bromic acids occurs, however, at the 6 position (53) to give the thermo- ynamically more stable zl -iminium salt (116), as shown by UV spectro- <=opy, = 274-278 m x. 

Both chloric and bromic acids are strong acids in aqueous solution (pX < 0) whereas iodic acid is slightly weaker, with pX 0.804, i.e. X 0.157. 

By oxidation with chromic acid, this is converted into cyclohexanone-3-carboxylic acid, in which the —CH. OH— group is converted into the —CO— group. This is converted into its ethyl ester and treated with magnesium methyl iodide, and the product, on hydrolysis, yields l-methyl-cyclohexane-l-ol-3-carboxylic acid, which is converted byhydro-bromic acid into 1-bromo-l - methyl - cyclohexane - 3 - carboxylic acid. When this is digested with pyridine, hydrobromic acid is eliminated and yields l-methyl-A -cyclohexane-3-carboxylic acid of the formula—... 

Brom-s ure, /. bromic acid, -schwefel, tn. sulfur bromide, -silber, n. silver bromide, -silizium, n. silicon bromide. -spat, n. bromyrite (AgBr). -stickstoff, tn. nitrogen bromide, -toluol, n. bromotoluene. -uber-trager, tn. bromine carrier. 

Halogenwasserstoff, m. hydrogen halide. -sSure, /. halogen hydracid, hydrohalic acid (general name for hydrochloric acid, hydro-bromic acid, etc.), -verbindung, /. hydrogen halide. 

The initial study by Berliner369 used R = Me, R = H, and R" variable, the reaction being carried out in a refluxing mixture of acetic acid (10 ml), hydro-bromic acid (4 mole, 48 %) and water (1 ml). The rate coefficients (the reaction was first-order in aromatic) are given in Table 95 and it appeared that the reaction... 

Bromated flour bromic acid potassium salt... 

Bromates, chlorates or iodates ignite in contact with phosphonium iodide at ambient temperature if dry, or in presence of acid to generate bromic acid, etc. Ignition also occurs with nitric acid, and reaction with dry silver nitrate is very exothermic. Interaction with antimony pentachloride at ambient temperature proceeds explosively. 

C. 3,5-Dibromosulfanilamide. The bromination of sulfanilamide is carried out in much the same way as the chlorination. The stirrer must be more efficient (Note 9) a glass stirrer with two sets of blades is satisfactory if run at high speed. Fifty grams (0.29 mole) of sulfanilamide is dissolved in a mixture of 850 ml. of water (Note 9) and 100 ml. (0.68 mole) of 40% hydro-bromic acid (Note 10). The solution is heated as above, but to 70-75°, and 65 g. (59 ml., 0.58 mole) of 30% hydrogen peroxide is added (Notes 2 and 11). A precipitate settles in 2 to 3 minutes, and the solution becomes yellow. The heat of reaction causes the internal temperature to rise without further application of heat to a maximum of 85-90° after 10 minutes by the end of the reaction time the temperature will have fallen to about... 

Bismuthic acid, 0228 Boric acid, 0144 Bromic acid, 0248 Chlorosulfuric acid, 3997 Chromic acid, 4229 Diamidophosphorous acid, 4547... 

Barium bromate, 0202 Barium iodate, Barium iodate, 0211 Bromic acid, 0248 Lead bromate, 0278... 

Bromic acid, 0248 Chloric acid, 3996 Hypochlorous acid, 3995 Iodic acid, 4424 Orthoperiodic acid, 4542 Perchloric acid, 3998 Periodic acid, 4425 See also HALOGEN OXIDES... 

Bromic acid Unknown 1 Eatty acids Unknown s... 

Orlova and co-workers "i reacted 1,2,3,5-tetranitrobenzene with hydrochloric and hydro-bromic acids to form picryl chloride and picryl bromide respectively. The same chemists treated 2,3,4,6-tetranitroaniline and 2,3,4,6-tetranitrophenol (121) with aqueous solutions of hydrogen halides to form 3-halo-2,4,6-trinitroanilines and 3-halo-2,4,6-trinitrophenols (122 and 123) respectively. 

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