Nitrous2000
Hazard to Self
Posts: 56
Registered: 1-11-2013
Member Is Offline
Mood: No Mood
|
|
Anyone have a simple tetrapropylammonium bromide?
Hi folks,
I’ve read the post on the butyl alcohol version but any simple synthesis to the propyl ammonium bromide version?
Can isopropyl alcohol be a starting point?
Thanks folks - I’m over 30 yrs from my chem degrees and I was a P Chem not a cook! 
Doug
|
|
|
njl
National Hazard
Posts: 609
Registered: 26-11-2019
Location: under the sycamore tree
Member Is Offline
Mood: ambivalent
|
|
I doubt the procedure would be very different for propyl alcohol. I also don't think IPA would be a good starting point unless you're willing to go
through an entire process to functionalize the primary carbon.
|
|
|
UC235
National Hazard
Posts: 565
Registered: 28-12-2014
Member Is Offline
Mood: No Mood
|
|
No, you'd need to start from n-propanol. Conversion to n-propyl bromide should be fairly trivial and preparation of isopropyl bromide and ethyl
bromide found eslewhere on this forum should work well and in high yield.
|
|
|
Tsjerk
International Hazard
Posts: 3022
Registered: 20-4-2005
Location: Netherlands
Member Is Offline
Mood: Mood
|
|
Tetraisopropyl ammonium bromide would have to go via triisopropyl amine, which is hard to make because of steric hinderance, making a quartenary out
of it would be impossible.
|
|
|
karlos³
International Hazard
Posts: 1520
Registered: 10-1-2011
Location: yes!
Member Is Offline
Mood: oxazolidinic 8)
|
|
Tetraisopropylammonium salts are impossible, wikipedia says the following: | Quote: | | Triisopropylamine is notable as being among the most sterically hindered amines currently known. |
So there is no way you can alkylate that even further.
If you even get to that, if you look at the wiki article, you'll discover the preparation of the trialkylamine is even not doable via the normal
routes.
[Edited on 20-2-2021 by karlos³]
|
|
|
draculic acid69
International Hazard
Posts: 1371
Registered: 2-8-2018
Member Is Offline
|
|
How is it made if not thru the normal routes?
|
|
|
Texium
Administrator
Posts: 4508
Registered: 11-1-2014
Location: Salt Lake City
Member Is Offline
Mood: PhD candidate!
|
|
Easy google
https://en.m.wikipedia.org/wiki/Triisopropylamine
|
|
|
clearly_not_atara
International Hazard
Posts: 2692
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
I would suggest looking into the paper which originally recommended tetrapropylammonium over tetrabutylammonium for this application:
https://pubs.rsc.org/en/content/articlelanding/1987/c3/c3987...
Since butanol is usually much cheaper and easier to get than propanol, it is probably helpful to know whether you can get away with tetrabutylammonium
in this case and what the disadvantages would be.
If you cannot buy n-propanol, any preparation of tetrapropylammonium bromide is going to be rather difficult. You can make propionaldehyde by the
pinacol rearrangement of propylene glycol with sulfuric acid, but you will need a few more steps to get tetrapropylammonium.
[Edited on 04-20-1969 by clearly_not_atara]
|
|
|
Nitrous2000
Hazard to Self
Posts: 56
Registered: 1-11-2013
Member Is Offline
Mood: No Mood
|
|
Tetrapropyl ammonium bromide
Thanks for the reply. Seems propyl bromide and tripropylamine are a one step with high yields... but am having trouble sourcing these.
One point I should make here is that my choice of agent is based on a paper detailing a static zinc-bromide (as opposed to the traditional flow-type)
battery that uses this as a bromide complexing agent to act as an electrolyte between plates.
Thanks
Doug
[Edited on 24-2-2021 by Nitrous2000]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
