Biodiesel (rapeseed oil methyl ester) was aged in a Rancimat device at a temperature of 110 °C and an air flow of 10 L/h. Time-resolved analyses applying gas chromatography−flame ionization detection, gas chromatography−mass spectrometry, and ion-exchange chromatography on the formation of aging products were performed. Formic and acetic acid, fatty acids with chain lengths from 5 to 18 carbon atoms, fatty acid methyl esters, and epoxides were quantified. After 12 h of aging, the concentrations of formic and acetic acid were 5600 ± 80 and 1360 ± 80 mg/kg, respectively. Fatty acid concentrations were in the range of <18−4200 mg/kg after 18 h of aging. Linoleic acid methyl ester and linolenic acid methyl ester (19 and 9.1 mass % of the non-aged fuel) were shown to be fully decomposed after 24 and 18 h of aging, respectively. After 51 h of aging, the concentration of oleic acid methyl ester (63 mass % of the non-aged fuel) decreased to 2.2 mass % and trans-epoxy stearic acid methyl ester and cis-epoxy stearic acid methyl ester reached concetrations of 5.9 and 0.7 mass %, respectively. The fuel composition shows only minor changes in early stages of aging, and a strong timely correlation of the formation of aging products with the end of the induction period of fuel was observed.

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Als reaktives, stark elektrophiles Vinylierungsmittel ergänzt die Titelverbindung die bekannten nucleophilen Vinylierungsreagentien. Mit katalytischen Mengen Silbertriflat reagiert sie zur Stammverbindung Vinyltriflat 1, mit Organometallverbindungen wie dem Vaska‐Komplex geht sie oxidative Addition, z.B. zu 2, ein.

121ChemInform Abstract 1,1,1-Trifluoroisopropyl bromide (I) reacts with triphenylphosphine (II) under rearrangement, forming the 3,3,3-trifluoropropylphosphonium salt (III) which is converted to the alkenes (VI) by Wittig olefination.