Chromyl bromide

Chromyl bromide Cr02Br2 is thermally unstable and little is known of its properties.222 It can be prepared from Cr02Cl2 and HBr in excess at low temperature, and by reaction of Cr03 with CF3COBr and HBr in the presence of P4Oi0. The existence of the iodide has been claimed but as mentioned in a review1372 of chromyl(VI) compounds this is unlikely. 

There is some reason for the belief that the interaction of chromic acid and acetyl bromide causes intermediate formation of unstable chromyl bromide, CrOjBra. 

Chromium dioxide, 928 Chromium fluoride, 932 Chromium tetrafluoride, 927 Chromium trioxide, 941 Chromyl bromide, 940 Chromyl chloride, 940 Chromyl halides, 933, 935, 938 Chromyl nitrate, 940 Chromyl perchlorate, 940 CitratoteUurates, 303 Cobalt complexes boron ligands, 99 Cobalt(ll) complexes reduction... 

Bromobenzaldehyde has been prepared by the oxidation of -bromotoluene with chromyl chloride/ by saponification of the acetal from />-bromophenylmagnesium bromide and orthoformic ester/ by the oxidation of ethyl -bromobenzyl ether with nitric acid/ by the oxidation of /j-bromobenzyl bromide with lead nitrate/ and by the hydrolysis of i-bromobenzal bromide in the presence of calcium carbonate. ... 

Chromyl chloride, 4054 Cobalt(II) bromide, 0263 Cobalt(II) chloride, 4048 Cobalt(III) chloride, 4122 Cobalt trifluoride, 4200 Copper(I) bromide, 0265 Copper(I) chloride, 4056... 

Chromium pentaphenyl bromide,1 (C6H5)5CrBr, is obtained by the action of phenyl magnesium bromide on anhydrous chromic chloride or chromyl chloride, the reaction in the former case probably taking the following course ... 

Bromides and iodides give rise to the free halogens, which yield colourless solutions with sodium hydroxide if the ratio of iodide to chloride exceeds 1 15, the chromyl chloride formation is largely prevented and chlorine is evolved.J Fluorides give rise to the volatile chromyl fluoride, Cr02F2, which is decomposed by water, and hence should be absent or removed. Nitrites and nitrates interfere, as nitrosyl chloride may be formed. Chlorates must, of course, be absent. 

Chloride in the presence of bromide Warm the solid mixture with a little potassium dichromate and concentrated sulphuric acid in a small distilling flask (Fig. IV. 1), and pass the vapours, which contain chromyl chloride, into sodium hydroxide solution. Test for chromate, which proves the presence of a chloride, with hydrogen peroxide and amyl alcohol or with the diphenyl-carbazide reagent. 

Neither bromine nor iodine forms compounds analogous to chromyl chloride under any of the conditions given above cf. p. 31), consequently the presence of a chromate in the aqueous solution of the distillate obtained by distilling a chloride, bromide, or iodide, or a mixture of these, with potassium dichromate and concentrated sulphuric acid, is sufficient evidence of the presence of a chloride in the mixture investigated (see p. 106). 

Interestingly, the chromyl ion oxidizes bromide via an acid-dependent pathway and all the kinetic data are consistent with a one-electron mechanism. However, there... 

BROMURO de AZUFRE (Spanish) (13172-31-1) Combustible liquid. Reacts with moisture in air, steam, or oxidizers, emitting fumes of hydrogen bromide and sulfur dioxide. Reacts with water, forming hydrobromic acid and fumes of hydrogen bromide and sulfur dioxide. Violent reaction with strong oxidizers, chromyl chloride, diethylzinc, dimethyl sulfoxide, lead dioxide, nitric acid, potassium. Incompatible with hexafluoroisopropylide-neaminolithium, iron sulfide, nickel, red phosphorus. Attacks most metals in the presence of moisture. 

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