Ozonisation products

Other applications of high performance liquid chromatography mass spectrometry to the detection of organic compovmds are reviewed in Table 5.1. 

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Following a published procedure [1], but using 75 g of diene instead of the 12.6 g specified, the ozonisation product exploded under desiccation. Eight previous preparations on the specified scale had been uneventful. 

Polymeric alkene ozonides are shock-sensitive that of trans -2-butene exploded when exposed to friction in a ground glass joint. The use of GLC to analyse crude ozonisation products is questionable because of the heat-sensitivity of some constituents [4], Ozonides are decomposed, sometimes explosively, by finely divided palladium, platinum or silver, or by iron(II) salts [5]. Individually indexed compounds are ... 

Ion exclusion chromatography has been applied to the determination of the following organic compounds and anions ozonisation products, carboxylic acids phosphate, nitrite, nitrate, silicate, bicarbonate, tartrate, malate, malonate, citrate, glycollate, formate and fumarate, arsenite, arsenate, chloride, bromide, iodide, thiocyanate and sulphate carbonate and also the cation arsenic. 

Applications of this technique are growing and include the analysis of mixtures of pesticides and herbicides, including oiganophosphorus, phenoxyacetic acid, caibamate, urea types, mixtures of various types of organic compounds, alkylbenzene sulphonates, polyethylene glycols, nonylphenyl ethoxylates, dioctadecylmethyl ammonium, ozonisation products and chlorination products. 

Ozonisation products Study of effect of ozonisation rate of water on degradation of impurities in notable [198]... 

Other organic compounds that have been determined in potable waters include pentachlorophenol, phthalic acid esters, diglycidyl ether, phenols, 4-aminophenol, ethylene glycol dinitrate, acrylamide, thiafluron, azine herbicides and ozonisation products (Table 4.4). 

Figure 5.6 Relationship between 1,2 content of butadiene and its amount of 1,6 hexane diol in the ozonisation products. Source Author s own files...

Oxalacetate, determination of 60-65 Oxalate, determination of 60-65 Ozonisation products, determination of 216, 217... 

Harries and Comberg have also supplied much evidence, which, taken with the above-mentioned researches, places the chemical isomerism of citronellol and rhodinol practically beyond dispute. By ozonisation experiments decomposition products were obtained, which proved that natural citronellal, obtained from citronella oil, is a mixture of about... 

The product of ozonising benzene exhaustively is extremely explosive at the slightest touch [1], The structure is not well defined as previously thought, but is probably polymeric [2],... 

Interaction of alkenes with ozonised oxygen tends to give several types of products or their polymers, some of which show more pronounced explosive tendencies than others [1]. The cyclic ge/n-diperoxides are more explosive than the true ozonides [2], It has been calculated that ozonisation of the endothermic /rara-stilbene (AH°f +135.4 kJ/mol, 0.78 kJ/g) would give, in the event of decomposition of the unstable ozonide, an exothermic release of 1.41 kJ/g which would attain an adiabatic decomposition temperature approaching 750°C with a 27-fold pressure increase in a closed vessel [3],... 

Benzene, aniline and other aromatic compounds give explosive gelatinous ozonides, among other products, on contact with ozonised oxygen. 

During work-up of the products of ozonolysis of R- and S-citronellic acids, a substantial quantity of the highly explosive trimeric acetone peroxide (3,3,6,6,9,9-hexamethyl-l,2,4,5,7,8-hexoxonane) was unwittingly isolated by distillation at 105-135°C to give the solid m.p. 95°C. The peroxide appears to have been produced by ozonolysis of the isopropylidene group in citronellic acid, and presumably the same could occur when any isopropylidene group is ozonised. Appropriate care is advised. 

Excess ozone should be avoided since further oxidation may occur. Conveniently a wash bottle charged with potassium iodide solution and acetic acid is attached to the outlet of the reaction vessel the completion of ozonolysis is indicated by the sudden extensive separation of iodine. Alternatively the flow of ozonised oxygen may be interrupted, and a drop of the solution removed and placed upon a white porcelain tile and allowed to mix with a drop of tetranitro-methane when the production of a yellow coloration is indicative of the presence of unreacted alkene. 

The solvent used in the latter case is dry ethyl chloride, which must be replaced by methanol before hydrogenation. Methanol when cooled to about — 20 °C is not attacked by ozone and can in many cases be used as the ozonisation solvent. In such cases the main product of addition of ozone to the alkene is not the usual ozonide, but is the methoxyhydroperoxide which, however, is also reductively cleaved to the aldehyde on hydrogenation. This ozonisation process may be mechanistically summarised as follows ... 

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