bobpage
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Isomerisation without heat?
If parsley seed oil is taken and heated.. from the boiling points of distillation it is about 50% pinene and 50% apiol/myristicin. Further separation
would require vacuum however, since it starts to burn after the pinene comes over, the temp jumps to 240oc.
If the pinene parts are removed and NaOH in IPA added (5 eq), the oil turns red almost straightaway. Does this mean these compounds can isomerise
without reflux? Or is it just something else in the mixture that is reacting?
Literature says that isomyristicin is a pale yellow oil. It seems hard to find any info on what colour isoapiol should be.
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kclo4
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Isomerisation without heat could have occurred, but it probably wasn't complete - after all they say reflux for a reason, right?
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turd
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| Quote: | Originally posted by bobpage
If the pinene parts are removed and NaOH in IPA added (5 eq), the oil turns red almost straightaway. Does this mean these compounds can isomerise
without reflux? Or is it just something else in the mixture that is reacting? |
Sounds more like polymerisation than anything else. Do yourself a favor and shop for a vacuum pump so that you can work on clean substrates.
| Quote: | | Literature says that isomyristicin is a pale yellow oil. |
Depends on the cis/trans ratio. I think trans is a solid at RT.
| Quote: | | It seems hard to find any info on what colour isoapiol should be. |
Probably yellowish crystals.
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Baphomet
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Thanks turd!
I will seek out such equipment, though it scares me 
Do you know if steam distillation would suffice? I know it is used to extract these oils from natural plant matter.. but is it any good for separating
the fractions?
\"Who ARE you? You\'re like the drummer from REO Speedwagon - nobody knows who you are\" from \'Employee of the Month\'
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not_important
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Steam distillation, and co-distillation in general, isn't much good at fractionation of substances with boiling points within a 100 degrees of each
other - exception being when one component associates strongly with water and the other doesn't as with ortho+para nitrophenol.
This is because co-distillation depends on the partial pressures of the co-distillnt (H2O) and a component in the mix summing to atmospheric pressure.
So it A has a partial pressure of say 20 mm, and B's is 25 mm, they distill over in the ration of their pp 20:25. That's what make steam
distillation useful for obtaining essential oils, which are mixtures of substances of different boiling points.
If you tweak around with a heated column you can get some separation, or better stated concentration, of components; but not very effectively and it's
a real bother.
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