502-26-1Relevant articles and documents
Skeletal isomerisation of oleic acid over ferrierite in the presence and absence of triphenylphosphine: Pore mouth catalysis and related deactivation mechanisms
Wiedemann, Sophie C.C.,Stewart, Joseph A.,Soulimani, Fouad,Van Bergen-Brenkman, Tanja,Langelaar, Stephan,Wels, Bas,De Peinder, Peter,Bruijnincx, Pieter C.A.,Weckhuysen, Bert M.
, p. 24 - 35 (2014)
The formation and nature of coke (precursor) species has been studied during the skeletal isomerisation of oleic acid catalysed by protonated ferrierite, in the presence and absence of a triphenylphosphine promoter. UV-Vis and FT-IR spectroscopic analyses of the spent catalyst materials, complemented by NMR and mass spectrometry of the coke deposits extracted after HF dissolution, provide new insights into the deactivation mechanisms. Initial high catalyst activity and selectivity are quickly lost, despite conservation of the framework integrity, as a result of severe deactivation. Pore blockage is detected very early in the reaction, and only the pore mouth is actively employed. Additionally, polyenylic carbocations formed by hydrogen transfer reactions poison the active sites; they are considered to be the precursors to traces of condensed aromatics detected in the spent catalyst. Dodecyl benzene is the major coke constituent, and its precursor probably also competes for the active sites.
Synthesis of δ-stearolactone from oleic acid
Cermak, Steven C.,Isbell, Terry A.
, p. 243 - 248 (2007/10/03)
δ-Stearolactone was prepared from oleic acid using concentrated sulfuric acid under various conditions in the presence of polar, nonparticipating solvents. δ-Stearolactone was formed in as high as 15:1 ratios over the thermodynamic product, γ-lactone, in the presence of methylene chloride, 100% wt/vol, at room temperature with two equivalents of sulfuric acid for 24 h. This procedure is applicable to other olefinic fatty acids such as estolides and fatty acid methyl esters. Temperature plays a role in the regioselectivity of the cyclization for γ-lactone, as lower temperatures (20 °C) gave higher δ/γ ratios. At higher temperatures (50 °C) in the presence of sulfuric acid and methylene chloride the yield of lactone was 75% but with a δ/γ ratio of only 0.3:1. Cyclization of oleic acid to lactone also occurred with other acids. Oleic acid underwent reaction with perchloric acid, one equivalent, in the absence of solvent at 50 °C, which yielded γ-lactone in a modest yield with a 3.1 δ/γ ratio. The same temperature effect was observed with perchloric acid that was observed in the case of sulfuric acid. Because δ-stearolactone is much more reactive than the corresponding fatty acid, fatty acid ester, or γ-lactone, we believe that it will be a useful synthon for many new industrial products including new biodegradable detergents.
