| Pages:
1
2 |
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
@Crowfjord:
Thanks a bunch, that settles that bit, as far as I'm concerned. Saved. 
Next, some questions on work-up from a poly acid catalysed conversion of α-pinene to α-terpineol acetate in GAA.
|
|
|
Crowfjord
Hazard to Others
Posts: 390
Registered: 20-1-2013
Location: Pacific Northwest
Member Is Offline
Mood: Ever so slowly crystallizing...
|
|
If I were to try, I think I would crash out the phosphotungstic acid with hexane or something similar. After filtering or decanting, add water to
separate the nonpolars. Wash the nonpolar with bicarbonate, water, then brine. Dry and remove solvent, then distillation should separate the desired
ester and alcohol, as they have fairly higher boiling points than the starting compound and side products.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by Crowfjord  | | If I were to try, I think I would crash out the phosphotungstic acid with hexane or something similar. After filtering or decanting, add water to
separate the nonpolars. Wash the nonpolar with bicarbonate, water, then brine. Dry and remove solvent, then distillation should separate the desired
ester and alcohol, as they have fairly higher boiling points than the starting compound and side products. |
| Quote: | The homogeneous reactions were performed by
adding monoterpene (0.3 mol l−1) to a 0.003–0.012
mol l−1 H3PW12O40 solution in acetic acid or an
HOAc/H2O mixture pre-thermostatted at 15–60◦C.
At appropriate time intervals, aliquots were taken,
diluted with hexane (1/10 v/v) to precipitate the heteropoly
acid and then analyzed by GC. |
The catalyst is suspended on silica (Aerosil 20), so it seems more logical to filter off the silica/acid first, at least to me.
What worries me a bit is that there's such a lot of GAA to get rid off: only 0.3 M of α-pinene to start with... Probably have to distil most of the
GAA off, then wash several times with water to remove the last bits of GAA. Final rinse with NaHCO3 suspension maybe...
[Edited on 8-12-2015 by blogfast25]
|
|
|
Crowfjord
Hazard to Others
Posts: 390
Registered: 20-1-2013
Location: Pacific Northwest
Member Is Offline
Mood: Ever so slowly crystallizing...
|
|
That's right. I was assuming use of the homogeneous version, without the silica support. You're probably right about the acetic acid, too. It may be
simpler to just distill it off, considering the large amount.
|
|
|
| Pages:
1
2 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
