PubMed · 10815205
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J K Harper, A M Arif, D M Grant. 2000-04-15. cis-Verbenol.. https://doi.org/10.1107/s010827019901570x
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The primary goal for the study presented here was the preparation and characterisation of enantiomeric pure chlorobornane standards (Toxaphene). In this context, we partially modeled the procedure for Polychloropinene production in the former USSR. The initial reaction was ionic addition of hydrogen chloride to (1S)-alpha-pinene resulting predominantly in (1S)-2-endo-chlorobornane. Further photochlorination gave mixtures of chlorinated terpenes with different average content of Cl per molecule. The resulting mixtures were separated on a silica-gel column and a number of known hepta to decachlorobornanes were identified in fractions with the help of NMR and GC (using electron capture and mass spectrometric detection)--but in very unusual ratios as compared to the technical Toxaphene mixture formerly produced by Hercules (USA). Also several previously unknown congeners were isolated or detected. Three of the isolated congeners were obtained in crystalline state and X-ray crystallography showed their enantiomeric purity.
Although poppy seed oil is an expensive article of trade, no literature about identification methods for adulteration with cheaper vegetable oils, like sunflower oil, has been published. This kind of adulteration is a challenge for routine analytical methods, such as the determination of fatty acid composition, because of almost similar fatty acid ratios. The detection of adulteration of poppy seed oils with sunflower oils at different levels (5-40%, w/w) by using SPME-GC-MS and MALDI-ToF-MS is the subject of our investigation. With the mentioned SPME-GC-MS method, it was possible to detect an admixture of sunflower oils in all relevant (5-40%) amounts by using alpha-pinene as a marker compound. Admixture of sunflower oil with high levels of triolein (high-oleic acid type) could be undoubtedly detected by MALDI-MS down to the 5-10% level. In contrast, adulteration of pure poppy seed oil by "standard" sunflower oils remained indistinguishable using this MALDI-MS.
The gas phase sabinene + OH reaction is studied both experimentally and theoretically. Product yields from the reaction of sabinene with OH radicals have been measured in the absence of NOx in the UCC chamber (Cork, Ireland) and in the presence of NOx in the LISA chamber. Three primary carbonyl compounds were observed and quantified: acetone in [(24 +/- 6)%], formaldehyde in [(25 +/- 6)%] and sabinaketone in [(20 +/- 6)%]. The simultaneous quantification of these compounds is one of the major results of this work. The mechanism of product formation for this reaction has been studied using the quantum chemical DFT-B3LYP (6-31G(d,p) method. According to these calculations, the H-atom abstraction channel from sabinene by OH in the initial oxidation step may be taken into account to explain the acetone production. Sabinaketone and formaldehyde are mainly products of the addition channels of OH on the -C=CH2 double bond of sabinene. This is the first theoretical work on the title reaction.