problems with distilling iso

[Snakebyte]

Swim is having trouble distilling his 300mL of isosafrol because his vacuum is not perfectly constant.  He is using a converted refrigerator pump which fluctuates between 26" and 27" and a 1 liter RBF.  When his temperature gets to the point where something looks like it's to come over, his vacuum will fluctuate up to 27" and his iso foams up his column.  When he turns down the temp, nothing comes over.  There seems to be no happy medium to distill at.  Any suggestions other than buying a pro vacuum?  BTW, swim froze his safrol to purify it which worked well.  Swims iso is a dark brown and smells minty like menthol or something.

[Belial]

You could just do away with the vac altogether.

[Snakebyte]

Do u know if that will cause any of the iso to to decompose at that temp?  Some posts say that it will.

[Antibody2]

i wouldn't distill it without a vac - no way

try using a column so when it foams up it has some head room, or put less in the flask. oir use a biigger flask

If the foaming is persistant Ab2 has found that disolving your iso in DCM and washing the post iso rxn mix w/ H2O a couple times can help remove any soap that may have been formed during the isomerization of your freezer purifiied sassy, but it is a pain in the ass.

[MDMA_AcTIvEsTS]

[Rhodium]

Neither safrole or isosafrole will decompose if distilled without vacuum. If you leave the vacuum out you will also get a lot better fraction separation, as that is one of the trade-offs with vacuum distillation - the boiling points of different substances come closer together. Also, you are more likely to experience insane bumping of the liquid under vacuum.

I have no idea about which impurities you are talking about which would cause extensive decomposition at atmospherical pressure distillation. If you have any substance to that argument, Mr. MDMA_AcTIvEsTS, please step forwards with them.

[abolt]

Chief.............maybe some folks are opening up their distillation setups whilst they are still hot and are getting tar formations and yield losses as a result.

Just a thought

[Snakebyte]

Rhodium...let me get this straight.  You say not to distill isosafrole with a vacuum because it you can get better seperation?  This will NOT destroy any of the isosafrole?  Then why is there so many posts saying to make sure u use a vacuum?  I don't know why u mentioned impurities...my post said nothing about any impurities.

[Rhodium]

The impurity question was directed towards MDMA_AcTIvEsTS.

I say that (iso)safrole can be distilled without a vacuum without any serious decomposition, people claiming otherwise may have had bad experiences distilling sassafras oil without a vacuum, but as natural oils contain so many components, it is not surprising if they got some tar in the end doing so.