Chromium sodium azide

Reaction with Sodium Azide and Chromium Trioxide... 

The reaction of steroid alkenes with sodium azide and chromium trioxide afforded tram-azi-dohydrins, often accompanied by a-oxo azides. A mechanism in which chromyl azide is involved is probably operating. Complete regioselectivity as well as simple and induced diastereoselectivity are generally observed, as determined by II-NMR analysis9. 

CHROMIUM CHLORIDE OXIDE (14977-61-8) A powerful oxidizer. Violent reaction with water, producing hydrochloric and chromic acids, and chlorine gas. Potentially violent and explosive reaction with reducing agents, acetone, alcohols, calcium sulfide, combustible materials, gaseous or liquid ammonia, ethers, nonmetal halides, fuels, nonmetal hydrides, fluorine, organic matter, organic solvents, phosphorus, phosphorus trichloride, sodium azide, elemental sulfur, sulfur monochloride, turpentine, urea. Decomposes slowly in light. 

Cobalt chloride in diglyme is a useful catalyst for benzylic [22a] and allylic [22b] oxidation under mild conditions. The addition of sodium azide to oxidations catalyzed by transition metal acetylacetonates, heteropolyacids, phtha-locyanines, bis-(pyridylimino)isoindolines, porphyrins and Schiff bases significantly enhances the rates of the low-temperature catalytic oxidation of alkanes [22c]. Ethylbenzene is slowly oxidized by air in MeCN in the presence of catalytic amount of chromium trioxide [23]. Complexes of Fe(III) and Co(II)... 

The compound was finally made by reacting chromium nitrate in a water-free ethanoHc solution with solid sodium azide [144]. Basic azides which are more or less water soluble are obtained as hydrolysis products of Cr(N3)3... 

All phases of coordination chemistry are encompassed by the complex chromium(III) azides. A yellow, crystalline salt of the composition [Cr (NH3)6] (N3)3, for example, is not a true azido complex but the azide salt of the hexammmechromium(III) cation. It is soluble in water the heated solution aquates over a red intermediate, aquopentamminechromium, to chromium hydroxide. The dry salt explodes in the match test. Similarly explosive is the neutral complex triamminetriazidochromium(III), [(NH3)3Cr (N3)3]°, an olive-green, crystalline solid which is, expectedly, insoluble in water and organic solvents it explodes thermally within 25 sec at 250°, and within 1 sec at 300°C, and also on impact [145]. The compound was made by heating a solution of 10 g hexamminechromium perchlorate, 10 g ammonium sulfate, and 50 g sodium azide in 300 ml water for 90 min. 

An anion complex, the hexaazidochromate(III), [Cr (N3)6] ", was isolated as the violet crystalline tetrabutylammonium salt. The complex is acetone soluble and decomposes at 255°C as with other azido complexes with large organic cations, no impact sensitivity was noted. To make it, chromium chloride hexahydrate was digested in 1 N sulfuric acid for 1 hr with excess dry sodium azide and then precipitated with a tetrabutylammonium salt [139]. 

When the steel contains manganese, permanganate is also formed and must be reduced by addition of sodium azide before proceeding to the test for chromium (compare page 192). 

Evaporate a portion of the solution, containing 20 to 50 fig of chromium, with a few drops of concentrated phosphoric acid to fumes. Cool and oxidise with 1 ml of 1 per cent potassium permanganate solution by heating on a water-bath for twenty minutes. Make slightly alkaline with dilute sodium hydroxide solution, add 5 per cent sodium azide solution drop by drop to decolorise the excess of permanganate and allow to simmer on a hot-plate for ten minutes. Cool, filter, acidify with 5 ml of dilute sulphuric acid, add 2 5 ml of diphenylcarbazide solution (0 25 per cent in 25 per cent ethanol) and make up to 25 ml. Allow the solution to stand for five minutes and measure the extinction at 540 mfi in a spectrophotometer. Carry out a blank determination. Read the number of milligrams of chromium equivalent to the observed extinction of test and blank from a calibration graph. 

Aq sol ns of sodium chromium azide did not react with Cr or N3 but with AgNOt gave an expl complex salt. The sodium chromium azide is considered to be the Na salt of chromihy-drazoic acid, HsCr(N3)6, but this acid was not isolated because it decomposed too readily. Attempts to obtain it by the methods of Wohler Martin (Ref 4) failed... 

The mixture 258 was converted to the unstable benzenesulfonyl aziridine 259 by treatment with an excess of benzenesulfonyl azide in benzene. Ace-tolysis of 259 with acetic acid and sodium acetate at room temperature for several days afforded the crystalline mixture of diastereoisomers represented by the formula 260. The aziridine rearrangement was regiospecific and 260 was the only product detected during this rearrangement. Lithium aluminium hydride reduction of 260 followed by acetylation yielded the mixture 261 in 85% yield. Selective hydrolysis of 261 afforded 262 in quantitative yield. The diastereoisomeric mixture 262 was converted into the diols 263 by hydrogenolysis. The diol mixture was oxidized with chromium trioxide... 

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