Hypobromite, potassium sodium

Hypobromites, the salts of hypobromous acid, do not keep well because they gradually disproportionate to bromide and bromate. Solutions are best prepared as needed from bromine and alkafl with cooling. Because disproportionation is catalyzed by cobalt, nickel, and copper (70), these impurities should be avoided. SoHd alkaline earth hypobromites, or more properly, bromide hypobromites such as calcium bromide hypobromite [67530-61 CaBr(OBr), have been known for many years, but the pure crystalline hydrates sodium hypobromite pentahydrate [13824-96-9] NaOBr 5H20, and potassium hypobromite tribydrate [13824-97-0], KOBr 3H20, were not described until 1952 (71). Hypobromites are strong bleaching agents, similar to hypochlorites. 

Appropriate pyrido[2,3-d]pyrimidin-5-ones with formyl groups in the 6-position have been oxiized to piromidic (68) and pipemidic (69) acids, or to intermediates for these, using moist silver oxide, chromium trioxide (potassium dichromate), potassium permanganate or, alternatively, sodium chlorite/hydroxylamine-O-sulfonic acid. 6-Acetyl groups have been similarly oxidized using sodium hypobromite in aqueous dioxane, whilst 2-acetyl groups give dimethylaminomethylene derivatives en route to 2-pyrazolylpyrido[2,3-d]pyrimidines. 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

Brom-jod, n. iodine bromide, -kalium, n. potassium bromide, -kalzium, n., kalk, tn. calcium bromide, -kampher, tn. bromo-camphor, Pharm.) monobromated camphor, -kohlenstoff, tn. carbon (tetra)bromide. -korper, tn. Colloids) "bromide body (bromide ion), -kupfer, n. copper bromide, lauge, /. bromine lye (solution of sodium hypobromite and bromide made by passing bromine into sodium hydroxide solution), -lithium, n. lithium bromide. -Idsung, /. bro-nune solution, -magnesium, n. magnesium bromide. -metall, n. metallic bromide. 

Initial halogenation of the oxime can use chlorine, hypobromite, bromine, or A-bromoacetamide. " Oxidation of the a-halonitrosoalkane can be achieved with nitric acid, nitric acid-hydrogen peroxide, " atmospheric oxygen, ozone, or a peroxyacid. Reduction of thea-halonitroalkaneis achieved with sodium borohydride or by catalytic hydrogenation, although potassium hydroxide in ethanol has been used for the conversion. 

G. Meillere, and A. Job and J. Clarens prepared a soln. of hypobromite, suitable for estimating urea in urine, by mixing eau de Javelle with an aq. soln. of potassium bromide and A. Fouchet mixed a soln. of 42 grms. of sodium bromide, and 8 5 grms. of sodium chlorate made to 100 c.c. with water, with a soln. of 50 c.c. of hydrochloric acid and 50 c.c. of water he then heated 30 c.c. of the first solution... 

A. J. Balard 6 prepared a soln. of sodium hypobromite, NaOBr, by working in a similar manner to the process employed for the hypochlorite. When bromine is gradually added to soda lye, the bleaching power increases up to a maximum, and after that decreases owing to the conversion of the hypobromite into bromate. A. J. Balard also described a similar product, potassium hypobromite, obtained by the action of bromine on potassium carbonate. 

Cognate preparation. 3-Aminopyridine. Prepare a cold sodium hypobromite solution from 32 g (10 ml, 0.2 mol) of bromine and 25 g (0.62 mol) of sodium hydroxide in 250 ml of water. Add in one portion 20 g (0.163 mol) of finely powdered nicotinamide (Expt 6.169) and stir vigorously for 15 minutes. Warm the solution in a water bath at 75 °C for 45 minutes. Isolate the crude product by continuous ether extraction (Section 2.22) of the cooled reaction mixture after saturation with sodium chloride. Dry the extract over potassium hydroxide pellets and remove the ether. Crystallise the dark residue from a 4 1 mixture of benzene-light petroleum (b.p. 60-80 °C) with the aid of decolourising charcoal. The yield of almost colourless product, m.p. 63 °C, is 9.3 g (61%). 

Orthanilic acid was first made by the reduction of nitro-benzenesulfonic acid by ammonium sulfide.2 This reduction has also been carried out electrolyticallv, and by the use of iron or zinc.3 The acid has also been made by the rearrangement of phenylsulfamic acid,4 by the action of sodium hypobromite upon potassium o-carbaminebenzenesulfonate,5 by the reduction of the mixed nitrobenzenesulfonic acids followed by separation of the isomers,6 by the action of methyl alcohol upon o-nitro-phenylsulfurchloride,7 by the action of acid upon diacetyl diphenylsulfamide,8 by the debromination of />-bromoaniline-e-sulfonic acid,9 by the reduction of 1,2,6-aminothiophenolsulfonic acid,10 and by the hydrolysis and reduction of e-nitrobenzene-sulfonyl chloride, which was obtained from di-o-nitrophenyl-disulfide.11... 

Methyl 3-bromopropiolate has been prepared by esterification of 3-bromopropiolic acid with methanol and sulfuric acid for 6 days (75% yield),4 the starting bromo acid being prepared by bromination of propiolic acid with aqueous potassium hypobromite.6 This reaction is particularly delicate to control, giving erratic results. Moreover, direct bromination of methyl propiolate with sodium hypobromite2 could not be reproduced. 

Potassium hypobromite, KOBr.—The hypobromite can be prepared from the hydroxide or carbonate by the action of bromine, or from the bromide by electrolysis, by methods analogous to those described for sodium hypobromite. 

Sodium aquo ferrocyanide,2 Na3Fe(CN)s.H20, results when sodium nitroprusside reacts with hydroxylamine, etc., or when the salt is oxidised by potassium hypobromite or hydrogen peroxide. 

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