Azide Hydrates

The crystal structures of the metal azide hydrates and pertinent references are summarized in Table III. 

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The crystal structures of the azides have been reviewed by Choi [14] and tables of lattice dimensions are provided. He points out that the crystal structures of the metal azide hydrates are quite different fi-om those of the anhydrous forms. He also notes a correlation between structure and impact sensitivity to explosion, which increases with the asymmetry of the azide ion, in the sequence ... 

Automobile safety air bags use sodium azide [26628-22-8] NaN, for gas generation. It can be made from hydrazine by refluxing ethyl or Abutyl nitrite with hydrazine hydrate and sodium hydroxide in alcohol (209,210) ... 

Sodium azide (Eastman, 97-99%) is activated by dissolving 100 g of the salt in 400 ml of distilled water and stirring with 14 ml of hydrazine hydrate for 15 min. The solution is filtered and added dropwise to 4 liters of rapidly stirred, dry acetone. The solid is collected by filtration and washed with 150 ml of dry acetone. The fine powder (57-85 g) is dried under vacuum at 50° for 2 hr. Sodium azide is extremely toxic and the fine powder should be handled with care to avoid breathing the dust. 

The methyl ester (100, R = CH3), derived from this A-nor acid by treatment with diazomethane, is different from the ester (102) obtained either by Favorskii rearrangement of 2a-bromo-5a-cholestan-3-one (101) or by the action of cyanogen azide on 3-methoxy-5a-cholest-2-ene (103) followed by hydrolysis on alumina. The ketene intermediate involved in photolysis of (99) is expected to be hydrated from the less hindered a-side of the molecule to give the 2j -carboxylic acid. The reactions which afford (102) would be expected to afford the 2a-epimer. These configurational assignments are confirmed by deuteriochloroform-benzene solvent shifts in the NMR spectra of esters (100) and (102). ... 

Reaction of 5-chloro-l,2,4-triazolo[l,5-c]pyrimidines (165) with sodium hydroxide, thiourea, or hydrazine hydrate (79AJC1585) or with sodium azide (85EUP152841) also caused the displacement of the chlorine atom to... 

The central role of imperfections in mechanistic interpretations of decompositions of solids needs emphasizing. Apart from melting (which requires redistribution of all crystal-bonding forces, by a mechanism which has not yet been fully established) the decompositions of most solids involve the participation of atypical lattice constituents, structural distortions and/or surfaces. Such participants have, in particular instances, been identified with some certainty (e.g. excitons are important in the decompositions of some azides, dislocations are sites of nucleation in dissociations of a number of hydrates and carbonates). However, the... 

Oxo-3,4-dihydro-2-quinoxalinecarbonyl azide (134) with ethanolic hydrazine hydrate gave 1,2,4-triazino[5,6- ]quinoxalin-3(4/l)-one (136), presumably via the Curtius intermadiate (135) (reflux, 2 h %). ... 

Skim milk (35 g/L) and /1-lactoglobulin (5 g/L) solutions were prepared by dissolving skim milk powder and y6-lactoglobulin powder in distilled water and stirring at room temperature for 4 h. /1-Casein (5 g/L) had been hydrated in a phosphate buffer (100 mM, pH 8) and stirred at 4°C for one night [27]. Sodium azide (0.1%, wt/v) was added to prevent bacterial growth. 

The indium-mediated allylation of trifluoroacetaldehyde hydrate (R = H) or trifluoroacetaldehyde ethyl hemiacetal (R = Et) with an allyl bromide in water yielded a-trifluoromethylated alcohols (Eq. 8.56).135 Lanthanide triflate-promoted indium-mediated allylation of aminoaldehyde in aqueous media generated (i-airiinoalcohols stereoselectively.136 Indium-mediated intramolecular carbocyclization in aqueous media generated fused a-methylene-y-butyrolactones (Eq. 8.57).137 Forsythe and co-workers applied the indium-mediated allylation in the synthesis of an advanced intermediate for azaspiracids (Eq. 8.58).138 Other potentially reactive functionalities such as azide, enone, and ketone did not compete with aldehyde for the reaction with the in situ-generated organo-indium intermediate. 

It decomposed with vigorous gas evolution below 80° C at 5 mbar. A preparative reaction mixture of chloroacetaldehyde hydrate and sodium azide had previously exploded mildly on heating in absence of added water. 

In the course of studies on azide-tetrazole equilibria, some azido derivatives 73 of this ring system have been subjected to X-ray structure elucidation <2005JST(751)65>. These derivatives proved to be mainly planar and the least planar part of these molecules were the azide moieties. In both cases (72 R= H and Me), formation of hydrates were also observed. Crystallographic analysis of the trifluoromethyl compound was described by Lange et al. <1997APH299>, and structure elucidation of the nucleoside analogue 74 was reported by Stanovnik et al. <1998JHC513>. 

Performance tests consisted of loading DBX-1 as a transfer charge in U.S. Army M55 stab detonators. Standard M55 detonators consist of three separate explosive layers, pressed sequentially into a metal detonator cup as shown in Figure 6. The first layer is 15 mg of the stab initiation mix (NOL-130) it is a combination of lead azide, lead styphnate, barium nitrate, antimony sulfide, and tetrazene [l-(5-tetrazolyl)-3-guanyltetra-zene hydrate], pressed at 70,000 psi. The second layer is 51 mg of transfer charge, lead azide, pressed at 10,000 psi. Lastly, the third layer is 19 mg of output charge, RDX, pressed at 15,000 psi. 

Benzhy dr azide.1—24 g. (0-15 mole) of ethyl benzoate (p. 141) are heated for six hours under a small reflux condenser on the water bath with 9 g. of hydrazine hydrate.2 The solid crystalline cake which is formed on cooling is, after some time, filtered as dry as possible at the pump and washed with a little ice-cold methyl alcohol. If the yield is too small the filtrate is concentrated and heated again. 

The reaction of Curtius, which is especially to be preferred in the case of the higher members on account of the favourable solubilities of the intermediate products, involves as its first stage the preparation of the hydrazide from an ester (or acid chloride). The hydrazide is then converted, usually very readily, by the action of nitrous acid into the azide. In many cases it is more convenient to prepare the azide by treating an acid chloride with sodium azide previously activated with hydrazine hydrate.1 Azides easily undergo thermal decomposition, the two azo nitrogen atoms being eliminated as elementary nitrogen. In this way, however, the same radicle is formed as was invoked above to explain the Hofmann reaction ... 

No, the editor didn t know what this name meant either.) It means salts of the triva-lent anions of Group V, restricted in [1] to arsenides, antimonides and bismuthides and prepared by reaction of sodium pnictides with anhydrous halides of transition and lanthanide metals. This violently exothermic reaction may initiate as low as 25°C. Avoidance of hydrated halides is cautioned since these are likely to react uncontrollably on mixing. Another paper includes a similar reaction of phosphides, initiated by grinding [2], Nitrides are reported made from the thermally initiated reaction of sodium azide with metal halides, a very large sealed ampoule is counselled to contain the nitrogen [3],... 

Several types of corrosion inhibitors have been investigated in the last 20 years [53-55] these include calcium and sodium nitrites, sodium benzoate, sodium/potassium chromate, sodium salts of silicates and phosphates, stannous chloride, hydrazine hydrate, sodium fluorophosphate, permanganate, aniline and related compounds, alkalis, azides, ferrocyanide, EDTA and many chelating compounds. However, in terms of field practice and research data, nitrite-based compounds occupy a dominant position. 

Conditions 5% CH3CH-H2O, = 0.5 (NaC104), T = 20°C, unless otherwise indicated. If and are reported, the rate constants were directly measured from photochemically generated ions. If only log 5 is reported, the selectivity was measured by the azide clock procedure. X is the observed [azide adduct]/[hydration product] ratio extrapolated to 1 M NJ. 

Curtius and Rissom [41] prepared cupric azide by the action of an aqueous solution of sodium azide on an aqueous solution of cupric sulphate, obtaining the salt in a hydrated form. The anhydrous salt was prepared by Straumanis and Ciru-lis [125] in the form of dark brown, reddish sediment by reaction of lithium azide on cupric nitrate in an alcohol solution. Another method described by Curtius consists of reacting hydrazoic acid with metallic copper in an aqueous medium. 

Acetaldehyde, Axido Derivative(Azidoacetaldehyde or Triazoacetaldehyde), Ns.CHa CH0, very unstable oil, expl mildly on heating. Was prepd in impure state from chloroacetaldehyde hydrate and Na azide. Dec by KOH with violent evoln of ammonia nitrogen... 

The copper azide chloride, Cu(N3)a-3CuCla 6H,0 or Cu(Nj)a 3CuCla prepd by Straumanis Cirulis (Ref 16) expl at 207-8°. The hydrate cannot be dehydrated. Therefor the anhyd compd should be prepd from abs ale The general types of copper azide addn compds a)[Cu(N,) ] b)[Cu(N3)J c)... 

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