抄録
Highly unsaturated fatty acid esters carrying more than 4 nonconjugated double bonds changed their structure to the conjugated polyene form, when heated under interruption of air.
The compounds produced by heating at 200°C without solvent were linear and had the cis-cis-trans conjugated triene form showing absorption maxima at 266, 277 and 287.5mμ, whereas those prepared by treating at 215°C together with 10 times of microcrystalline wax consisted both of the linear and of the ring compounds, in nearly the same proportion.
In both cases, the conjugated triene compounds were all monomeric and the dimeric triene was never found.
When heated at 250°C without solvent the produced conjugated diene had the absorption maximum at 236mμ and consisted mainly of the dimeric compounds having the cyclohexane ring structure.
In contrast, the compounds treated at 250°C with microcrystalline wax included not only the dimeric conjugated diene, above described, but also the monomeric diene that may have the polycyclic form as well as cyclohexane ring in about the same ratio.
Polymer more than dimer was scarcely found under our experimental conditions.
