ODBAL
Harmless
Posts: 2
Registered: 9-11-2016
Member Is Offline
Mood: No Mood
|
|
Ozonolysis
Hi everyone,
This is my first post. I have just received a new ozone generator and I want to give a go at splitting some alkenes. Specifically I'd like to try
the ozonolysis of styrene mostly because it is a terminal alkene that would yield fairly distinctly identifiable carbonyl species.
My concerns are that I've never tried this reaction before, so I am unfamiliar with the work-ups. I have a set of glassware dedicated to peroxide
like stuff that I can put behind a blast shield.
If I wish to follow this up with a reduction of the ozonide, what might the procedure be like for say Zn/AcOH? or NaBH4? Do I just dump in a mixture
of the reducing agent after the reaction is finished?
|
|
|
Rhodanide
Hazard to Others
Posts: 348
Registered: 23-7-2015
Location: Ｔｈｅ ８０ｓ
Member Is Offline
Mood: That retro aesthetic
|
|
Quote: Originally posted by ODBAL  | Hi everyone,
This is my first post. I have just received a new ozone generator and I want to give a go at splitting some alkenes. Specifically I'd like to try
the ozonolysis of styrene mostly because it is a terminal alkene that would yield fairly distinctly identifiable carbonyl species.
My concerns are that I've never tried this reaction before, so I am unfamiliar with the work-ups. I have a set of glassware dedicated to peroxide
like stuff that I can put behind a blast shield.
If I wish to follow this up with a reduction of the ozonide, what might the procedure be like for say Zn/AcOH? or NaBH4? Do I just dump in a mixture
of the reducing agent after the reaction is finished? |
Here's a thread about Ozonolysis, it might help you, it might not. Cheers! Link: http://www.sciencemadness.org/talk/viewthread.php?tid=13467
|
|
|
zed
International Hazard
Posts: 2283
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
|
|
Ummm. Styrene. I'm not sure Styrene will do what you want it to.
Now, Iso-eugenol..... That can be done. Maybe even profitably.
Vanillin, produced from Iso-eugenol, is sometimes offered as "Natural Vanilla". It is after-all, produced by cleaving isomerized Clove oil. Eugenol
derived Vanilla, sells for a premium price.
https://www.google.com/patents/US2916499
And, the patent suggests, no reduction is required.
[Edited on 9-11-2016 by zed]
|
|
|
ODBAL
Harmless
Posts: 2
Registered: 9-11-2016
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by zed | Ummm. Styrene. I'm not sure Styrene will do what you want it to.
Now, Iso-eugenol..... That can be done. Maybe even profitably.
Vanillin, produced from Iso-eugenol, is sometimes offered as "Natural Vanilla". It is after-all, produced by cleaving isomerized Clove oil. Eugenol
derived Vanilla, sells for a premium price.
https://www.google.com/patents/US2916499
And, the patent suggests, no reduction is required.
|
That patent certainly has my interest, and may have to be a separate project in itself. However it seems to describe a different reaction in which
water or the protic solvent is involved. I'm more interested in the textbook reaction with formation of ozonide intermediate followed by a reduction.
Furthermore, I wonder what you mean about it not working? Are you referring to just what the patent says? I'm certain that if I am to obtain
benzaldehyde from styrene there will need to be a more traditional procedure, but it should be possible yielding formaldyde.
My rough expectations for this reaction are that:
I should ozonate a dilute solution of my ethylenyl compund until saturation under O3/O2 and with reduced temperature to enhance
ozone absorption and slow the rate of reaction.
After it is indicated that the solution has an excess of O3, further flushing with O2 and simply quenched (do I need TLC
monitoring here or is it that quick?) with a solution of dimethyl sulfide or thiourea.
And then separation with water/ether extraction.
Any tips (especially on safety) would be appreciated.
[Edited on 17-11-2016 by ODBAL]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
