Nitrated Compounds Research Articles

Isolation and identification of β-nitrostyrene from smoked chicken

Extraction and identification of β-nitrostyrene from smoked chicken is described. Commercially obtained smoked chicken was homogenised and extracted with chloroform-methanol (2:1). The extracts were fractioned by silicic acid column chromatography. The purified extract using thin-layer chromatography was identified by a colour reaction (this qualitative method for some nitrated compounds is developed this time), high pressure liquid chromatography and gas chromatography/mass spectrometry. The concentration of β-nitrostyrene in the smoked chicken was 94 ppb. The average recovery of added β-nitrostyrene was 107%. However, the toxicity of this material was not tested in the present paper.

Prediction of gas chromatographic retention indexes of polycyclic aromation compounds and nitrated polycyclic aromatic compounds

A previously derived equation for the prediction of chromatographic retention indexes for polycyclic aromatic compounds (PACs) was tested for application to 56 nitro-PACs. A new two-variable equation was derived that applies to a wide range of both PACs and nitrated PACs. The predicted retention indexes correlate highly to the experimentally measured values (r = 0.992). 23 references, 3 figures, 2 tables.

Evaluation of a thermionic detector for capillary supercritical fluid chromatography of nitrated polycyclic aromatic compounds

AbstractA thermionic detector was evaluated for capillary supercritical fluid chromatography of polar nitro‐containing polycyclic aromatic compounds (nitro‐PAC). Three modes of detector operation were studied. The best performance was obtained using a nitro‐selective mode of detection. Although linearity was confined to a narrow range for a given source current, the sensitivity was excellent; 20 pg injected for p‐nitrophenol gave a signal‐to‐noise ratio of 3. Conventional thermionic detection also produced good sensitivity; however, serious baseline drift was observed at high operating temperatures using density programming. A third mode, flame thermionic detection, was not acceptable because of low sensitivity. A number of nitro‐PAC were successfully chromatographed using density programming at 101°C. Hydroxynitropyrenes, nitropyrene quinones, and 9‐hydroxy‐2‐nitrofluorene, which could not be eluted in capillary gas chromatography, were successfully chromatographed here. Retention of these compounds increased sequentially on 50% n‐octyl‐, 5% phenyl‐, and 25% biphenyl polysiloxane stationary phases, respectively. Stationary phase interactions appeared to be more a function of the polar functional groups on the aromatic rings than of the hydrocarbon character of the compounds. Solute solubility in the mobile phase and volatility were additional factors contributing to the elution of these molecules. Finally, these results were used to identify a number of nitro‐PAC in a polar subfraction of a diesel particulate extract.

Research towards novel energetic materials

Abstract Compact, three-dimensional cage compounds containing optimum numbers of nitro groups as determined in theory by thermohydrodynamic calculations, constitute a class of explosive compounds more powerful than HMX. This is a direct result of high crystal densities, particularly in combination with high strain energies built into certain of the cage systems. The synthesis of polynitro cage compounds has progressed on several fronts, and is currently in the second stage of a three-stage effort. The first stage has seen the synthesis of forerunners of more highly nitrated cage compounds, as part of a broad strategy to develop the methodology for achieving the polynitration of cage molecules. The nitro cage compounds whose syntheses are in progress (second stage) and will be completed in the near future are expected to be energetic. These compounds, in turn, are expected to lead, in the third stage, to stil more highly nitrated cage compounds including those which will be signifficantly more powerful tha...

Determination of nitrated polycyclic hydrocarbons in aerosols using capillary gas chromatography combined with different electron capture detection methods

AbstractA method is described which allows the determination of subnanogram concentrations of mono‐ and dinitrated polyaromatic hydrocarbons with two to four ring systems in aerosol samples. High performance liquid chromatography is used to separate the nitro compounds from other classes of substances. Carbozoles elute in the same fraction. Both electron capture detection and negative ion chemical ionization mass spectrometry combined with capillary gas chromatography are used for quantification. Use of these two methods leads to a considerable improvement of selectivity and sensitivity for nitrated compounds. In contrast to the situation with a nitrogen‐sensitive detector, carbazoles do not interfere and detection limits in the order of 10–200 pg/m3 are possible. The applicability of the method is critically discussed. Determination of nitrated polyaromatic hydrocarbons in aerosol samples from an aluminum smelter serves as an example.

Synthesis of Bz-Phe(p-No2)-Val-Arg-pNA-and its specificity to thrombin-like enzymes: similarity of a commercial product S-2160 to the nitrated compound.

Abstract When Bz-Phe-Val-Arg-pNA, distributed by Kabi as S-2160, was synthesized independently in our laboratory, an unidentity was observed in the λmax values between our product and S-2160 although both compounds were indistinguishable by either thin layer chromatography (TLC) or high performance liquid chromatography (HPLC) under ordinary conditions. Further, thrombin cleaved S-2160 faster than our product. To solve the discrepancy both products were thoroughly analyzed, and we found that S-2160 has been distributed as a modified form at the Phe residue to be Phe(p-NO 2 ). Bz-Phe(p-NO 2 )-Val-Arg-pNA was then synthesized as an authentic sample, and the product was compared with the unmodified compound and with S-2160. From the kinetic data, it was confirmed that the nitrated compounds were more susceptible to thrombin than unmodified compound.

Action du monoxyde d'azote sur le trichloréthylène et sur le tétrachloréthylène

The Action of Nitrogen Monoxide on Trichloro‐and Tetrachlor‐Ethylene.Under the sun light and at room temperature nitric oxide reacts with trichlorethylene and tetrachlorethylene giving monomer nitroso nitrated compounds. These compounds can also be obtained through reaction of dinitrogen trioxide with trichlorethylene and tetrachlorethylene.The nitrating and oxidizing properties of nitric oxide can be considered through these reactions:– Trichlorethylene leads to: pentachlorethane,1,1,1,2‐tetrachlor‐2‐nitroethane, dichloracetic acid and 1,1,3,3‐4‐pentachloro‐4‐nitro‐1‐butene: CO2 and CO are also observed.–Tetrachlorocthylene gives : hexachlorethane, tetrachloro‐2pentaclorethyl‐1,2‐oxazetidine; carbon tetrachlorid and trichloracetylchlorid arc obtainetl in very little yiclcl. These results prove that oxidizing cleavage may occur.Kitric oxitl reacts giving nitrogen as main gazcous product, prouved by gas liquid chrornatography.

Rearrangements in the Diterpenoid Series. Part II. The Diazotization of Methyl 15-β-amino-13-isopropyl-17-noratis-13-en-18-oate

Treatment of methyl 15-β-amino-13-isopropyl-17-noratis-13-en-18-oate (1b) with sodium nitrite – acetic acid gives rise to a variety of products, including nitrated compounds and norketones. The structures of seven of the products have been established. The reaction of methyl 16-isopropylidene-7,17-secoacon-8(15)-en-18-oate (2) with nitrous acid and with dinitrogen tetroxide is described. A simple method for transforming isocyanates to primary amines is presented.

Determination of nitric acid in nitration solutions by means of the nitrate electrode

Determination of nitric acid in nitration solutions by means of the nitrate electrode was examined. For this purpose, the sample of nitration solution must be diluted to 100 times with water before the standard addition method is applied, because the assymmetric potential may change in the presence of nitrated organic compounds while the electrode slope (the increase of e.m.f. per ten-fold change in the nitrate content) remains almost unchanged if the concentration of sulfuric acid is kept constant.The electrode slopes are much affected by the presence of sulfuric acid when the concentration of nitric acid is relatively high. It is also affected by the presence of nitric acid when the concentration of sulfuric acid is high. But, when the pH of solution is adjusted to about 10 by the addition of sodium hydroxide, the electrode slope is almost constant and approximately equal to the theoretical value.

Electron‐impact fragmentation of aliphatic polynitro compounds

AbstractThe mass spectra of two series of aliphatic polynitro compounds are reported and discussed. The fragmentation patterns of aliphatic nitro and polynitro compounds are similar in that no appreciable molecular ion current is observed; however, there are several other features in the fragmentation of aliphatic polynitro compounds which differ from that of nitroalkane spectra. Both series of compounds studied‐C(NO2)x(CH3)4−x, where x = 4 to 0 and C2(NO2)x(CH3)6−x, where x = 6,4,2‐show a decrease in the number and intensity of alkylions with an increase in the NO+ and NO2+ ion current as x increases. The main ions resulting from the more nitrated compounds are [NO]+, [NO2]+, [CO2]+. and [CH3CO]+, whose noncharged counterparts are the principal species produced in the detonation of these compounds. This similarity of the products of the two processes suggests the use of mass spectroscopy for the investigation of the initial explosive processes. The principal fragmentation pathways of the polynitroalkanes have been elucidated by exact mass measurements and the observation of metastable ion transitions.

M. F. E. Turpin

M. FRANÇOIS ENGÈNE TURPIN, well known as the inventor of melinite, one of the high explosives used in shell-filling, died on Jan. 24 at Pontoise. We are indebted to a recent issue of La Nature for the following particulars of his life. After his birth at Rosendael in 1849 his parents moved to Paris, where, on leaving school, he began to study medicine. But he became interested in chemical research, aind it was not long before his natural skill in experimental work was publicly recognised by the bestowal upon him by the Paris Academy of Sciences of the Montyon prize for his invention of harmless colouring matters for children's toys, This invention presently involved him in some litigation, but, nothing daunted, he applied himself with energy to the study of explosives. Those were the days of black gunpowder, dynamite, and gun-cotton. The instability of nitrated organic compounds had rendered them unfit for use by the artillery and even unsafe to store in magazines. With the object of overcoming these difficulties Turpin decided to abandon the search for suitable material among aliphatic compounds and turned his attention to those of the aromatic series. After seven years of ceaseless toil he perfected a process for preparing a suitable high explosive from picric acid by the simple device of melting it in an oilbath and running it into moulds. When, shortly afterwards, a suitable detonator had been devised for use with the new explosive, the French Government purchased the new process from him; but the secret appears to have been treacherously revealed to a British firm by an artillery officer, whom Turpin vigorously denounced in a volume entitled “Comment on a vendu la m6linite.” For this indiscretion Turpin was prosecuted, and eventually condemned to prison on the charge of having revealed in his book secrets of importance to the national defence. After spending nearly two years in prison he was pardoned in 1893, and in 1901 he was completely restored to favour by being elected to serve as a technical adviser to the artillery. In this capacity he rendered invaluable service to France until after the War, when the State awarded him an annuity.