Thermal Reaction of Safflower Oil in the Presence of Organoiodine Compounds

Abstract

Safflower oil was heated at 200°C with 0.065mol/kg of the following organoiodine compounds : methyl iodide, methylene iodide, iodoform, ethyl iodide, 1, 2-diiodoethane, iodoacetic acid, 3-iodopro pionic acid, and 1-iodopentane. It was found that iodoform, 1, 2-diiodoethane, and iodoacetic acid among those organoiodine compounds used promote conjugation reaction. Moreover, the thermal reaction of safflower oil in the presence of those three iodine compounds was studied under various reaction conditions. The fatty acid compositions of reaction products were determined by means of GLC and UV methods. The results show that other reactinos occur such as the formation of octadecenoic acids, polymerization, and decomposition besides isomerization. Also, it is clarified that 1, 2-diiodoethane promotes isomerization most rapidly and secondly iodoform does.The components formed by side reactions such as decomposition, polymerization, and so on were analyzed by means of GC-MS and GLC method. The presence of ω-phenyl fatty acids and 18- (o-alkylphenyl) C18 fatty acids was confirmed and that of η-alkanes, alkyl iodides, and alkylbenzenes was presumed.The similarity of the substances formed in the thermal reaction with organoiodine compounds mentioned above to those with iodine reported in our previous work suggests that free iodine liberated from organoiodine compounds in the thermal reaction will play mainly the role of catalyst.