Nitrato ester

New prepolymers based on 3,3-bis (azidomethyl) oxetane (BAMO) and 3-nitratomethyl- 3-methy-loxetane (NMMO) are used in advanced pintle-controllable solid rocket motor applications. These polymers yield favorable propellant energy with the combination of nitrato esters and ammonium nitrate, and allow solid propellant designs to compete with liquid propellants in arenas of energy management, approaching true start-stop-restart operation. 

Table 4.12 presents the calculated energies of formation for the solid neutral species and salts based on the CBS-4M method (see Ch. 4.2.1). Furthermore we see from table 4.12 that for the nitronium ([N02]+) species the covalently bound form is favored over the ionic salt by 26.9 kcal mol 1 while for the nitrosonium species ([NO]+) the salt is favored over the covalent isomer by 10.5 kcal mol-1. This change from the preferred covalent form of —N02 compound (actually a nitrato ester) to the ionic nitronium salt can be attributed almost exclusively to the increased lattice enthalpy of the (smaller ) N0+ species (AffL(N0+ - N02 salt) = 31.4 kcal mol-1) (N.B. The difference in the ionization potentials of NO (215 kcal mol-1) and N02 (221 kcal mol-1) is only marginal). 

A processing advantage is achieved with the castable double-base systems a rocket chamber is filled with particulate nitrocellulose (casting powder), which then is treated with NG or a mixture of nitrato esters. The nitrocellulose is swollen by the nitrato ester to give the final propellant, a tough material with relatively low elasticity. 

The oxidative photoaddition of NNP to 3-butenyl chloride and bromide in the presence of perchloric acid gave 2-nitrato-5-azoniaspiro [4,5] decane perchlorate (306) in 38 and 46% yield, respectively165 (equation 146). The yield of the salt is obviously much higher, but it is difficult to extract from aqueous solution. The oxidative photoaddition to 3-butenol and its acetate gives 72-80% of the expected product 305, while that to various benzoate esters gives about 26-33% and that to p-toluenesulphonate gives no product. 

Circular dichroism of the nitrato (ONO) chromophore of the mono- and di-nitric esters of l,4 3,6-dianhydrohexitols was found to consist of two dichroic bands, one weak and positive, at about 265 nm, and a stronger band at —228 nm, which was positive for the endo-(R)-nitrato chromophore and negative for the exo-(S)-nitrato group.68 However, for l,4 3,6-dianhydro-D-glucitol dinitrate, which has both an endo and an exo nitrato group, both bands were positive, but [ ]ma r (+ 7,260) for the band at 225 nm was about half of the algebraic sum of this band for the di-endo (+ 18,400) and di-exo (—4,460) compounds. 

The infrared spectra (benzene solution) of the isohexide nitrates, as well as of their mixed nitric and p-toluenesulfonic esters, are well established. The positions of the v and the bands for the nitrato group are remarkably constant, at 1645 3 cm-1 and 1282 1 -1 (endo), and 1274 1 cm-1... 

It is well known that the low stability of nitrocellulose is often attributed to the presence of sulphates of cellulose, usually in the form of mixed esters f nitrato-sulphatcs (Vol. 11, pp. 293-298). A number of patents [I] havcaltempted E to obtain nitrocellulose free of sulphates by nitrating cellulose with nitrating mixtures composed of nitric acid and salts of nitric acid, such as magnesium nitrate [14] much in the way described in Vol. II, pp, 346-347. 

Cast pTopellaniN 5K7-5S8 Cast propellants, slurry 5RH-59()(II1/677) Cellulose 339-341 (11015-231,362-372) for nitration 339 (11/362-372) mixed esters (nitrato-sulphatcs) 342 (II 293)... 

NITRATO CALCICO (Spanish) (10124-37-5) A strong oxidizer. Violent reaction with reducing materials. Forms shock-sensitive mixtures with organic contaminants. Incompatible with combustible materials (wood, cloth, oil, grease, etc.), organics, and other easily oxidiz-able materials, chemically active metals, aluminum nitrate, ammonium nitrate, cyanides, esters, phosphorus, sodium hypophosphate, thyocyanates. Corrosive to many substances, including aluminum. 

NITRATO de COBRE (Spanish) (3251-23-8) A strong oxidizer. Violent reaction with reducing agents, combustible materials, acetic anhydride, ethers, potassium ferrocyanide, finely divided tin. The aqueous solution is a medium-strong acid. Incompatible with bases, acetylene, ammonia, aliphatic amines, alkanolamines, amides, alkylene oxides, cyanides, epichlorohydrin, esters, isocyanates, organic anhydrides, vinyl acetate. Attacks metals in the presence of moisture. 

NITRATO de ZIRCONIO (Spanish) (13746-89-9) A powerful oxidizer. Violent reaction with reducing agents, combustible materials, powdered metals, organic substances, acetic anhydride, tert-butylhydroperoxide, metal cyanides, thiocyanates, sodium acetylide. Incompatible with amines, ammonium hexacyanoferrate(II), boranes, cyanides, citric acid, esters, hydrazinium perchlorate, isopropyl chlorocarbonate, nitrosyl perchlorate, organic azides, organic bases, sodium thiosulfate, sulfamic acid. Incompatible with esters, many other substances. Attacks metals. 

The 0x0 (0 ) ligand is dominant in the coordination chemistry of osmium, participating in the VIII to IV oxidation states inclusive. The tetroxide OSO4 is the single most important compound of osmium OSO4 and the recently discovered [0s04] ion arc tetrahedral. The /ra 5-[0=0s —O] osmyl moiety displays an extensive chemistry, comparable with that of the uranyl 0=U=0 unit, and there is an extensive and unique cyclic oxo-ester chemistry (p. 584). There is surprisingly little information on hydroxo, aqua, sulfato, nitrato or phosphato complexes, but much recent work has been carried out on carboxylato species, and clearly much work remains to be done on the O-donor chemistry of the element. There are a reasonable number of sulfur-donor complexes but few with selenium or tellurium. 

Carbon-Oxygen Bond Formation. CAN is an efficient reagent for the conversion of epoxides into /3-nitrato alcohols. 1,2-cA-Diols can be prepared from alkenes by reaction with CAN/I2 followed by hydrolysis with KOH. Of particular interest is the high-yield synthesis of various a-hydroxy ketones and a-amino ketones from oxiranes and aziridines, respectively. The reactions are operated under mild conditions with the use of NBS and a catalytic amount of CAN as the reagents (eq 25). In another case, N-(silylmethyl)amides can be converted to A-(methoxymethyl)amides by CAN in methanol (eq 26). This chemistry has found application in the removal of electroauxiliaries from peptide substrates. Other CAN-mediated C-0 bondforming reactions include the oxidative rearrangement of aryl cyclobutanes and oxetanes, the conversion of allylic and tertiary benzylic alcohols into their corresponding ethers, and the alkoxylation of cephem sulfoxides at the position a to the ester moiety. 

Treatment of tri- -acetyl-D-glucal with trifluoroacetic anhydride and ammonium nitrate gives isomeric 2-deoxy-2-nitrato-glycosyl tri-fluoroacetates which, with base, undergo very efficient Grob fragmentation as indicated in Scheme 2. Glycal esters with 3, -cis... 

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