Illegal Parkinson - 19-10-2005 at 15:19
I made a post over at wetdreams basically saying that if it is possible to make EtOEt from ethanol than can an analogous reaction be done on IPA?
I mean I was all fired up to do this and all but the reply was that "DIPE" is probably the most prone to forming peroxides out of all the
ethers. So it was conceded that the risk involved in this idea rendered it redundant.
Does anybody have a published procedure to make "DIPE" from IPA 99% and conc H2SO4? I could not find a single procedure. Just holler if you
know anything. It goes beyond my comprehension and I just want somebody elses POV on the matter. Thanks
BromicAcid - 19-10-2005 at 16:04
If you make it might I recomend:
Stabilization of Isopropyl Ether.
A. C. Hamstead, L. S. VanDelinder;
J. Chem. Eng. Data; 1960; 5(3); 383-386.
Also, while looking up a procedure for what you wanted (which I didn't find) I found that isopropyl ether is fairly adept at extractions of all
sorts of things, for example, I didn't know that ethyl ether or isopropyl ether (when mixed with a small amount of their respective alcohols)
were good mediums to extract acetic acid from water solutions.
Attached is a little interesting document I found:
New Industrial Solvents Ethylene Dichloride, Dichloroethyle Ether, and Isopropyl Ether
H. R. Fife, E. W. Reid;
Ind. Eng. Chem.; 1930; 22(5); 513-515.
Attachment: ie50245a024.pdf (388kB)
This file has been downloaded 883 times
Illegal Parkinson - 19-10-2005 at 22:53
Thanks.
Eclectic - 20-10-2005 at 09:46
Stabilization of Isopropyl Ether.
A. C. Hamstead, L. S. VanDelinder;
J. Chem. Eng. Data; 1960; 5(3); 383-386.
Could you post this article?
Marvin - 20-10-2005 at 10:55
I have the feeling the tendency of isopropyl alcohol to eliminate would be something of a problem when trying to make this ether in high yeild.
Isopropylene anyone?
Illegal Parkinson - 20-10-2005 at 13:06
Judging on the basis of what is written in Vogel this would seem like a real possibility esp. at higher temps. However in a pragmatic sense, the risk
of forming explosive peroxides is the real worry. Just imagine performing the experiment and having the thing blow up in front of you.
garage chemist - 20-10-2005 at 13:23
The peroxide risk is only significant if you were to store the ether for more than a few days.
During production you don't have to worry about peroxides at all.
What's the big deal with everyone shouting "Peroxides!" as soon as someone says "Ether"? Formation of peroxides only occurs
if the ether is stored unstabilised for extended periods of time.
Diethyl ether, if properly stabilized by addition of a few KOH flakes or 25ppm BHT remains peroxide- free for over a year, even when air and light are
present.
Illegal Parkinson - 20-10-2005 at 19:40
In 'a treatise of organic chemistry' (1881) p564, it is written that "DIPE" is made from the action of silver nitrate [expensive]
on isopropyl-iodide [mutagenic]. 'The oil is a liquid bp 60-62 deg smell of peppermint'.
But the point being that it would seem as though isopropanol cannot be made into its corresponding ether by H2SO4.
[Edited on 21-10-2005 by Illegal Parkinson]
[Edited on 21-10-2005 by Illegal Parkinson]
[Edited on 21-10-2005 by Illegal Parkinson]
12AX7 - 20-10-2005 at 20:35
Can'tcha just add a few micrograms of manganese?
Tim
Marvin - 21-10-2005 at 02:56
Well spotted that man Parkinson but lets try and keep the chinease whispers down to a minimum. Silver Oxide. Ive just spent an hour trying to work
out why the nitrate would not form the higher boiling isopropyl nitrate, that would be why 
Tim, I doubt that would work.
12AX7 - 21-10-2005 at 06:24
Why not? Mn decomposes at least hydrogen peroxide..
Marvin - 21-10-2005 at 08:30
In fact I'm wrong.
It was my assumption that it would have to work the same way that caused me to discount it. It doesnt, which is why it does work.
Fe 2+ and Mn 2+ salts cause the ether to break apart into aldehyde and ethanol.
I'm unsure if adding a Mn2+ salt is a good idea as this might also catalyse the formation of the peroxides. I'm also unsure if the ether
would have to be wet to work.
Edit,
"The resulting aldehyde has to be removed to prevent a rapid back-formation of peroxides."
So it can be helpful for a purification step, but its not useful for long term storage.
[Edited on 21-10-2005 by Marvin]
mick - 21-10-2005 at 12:31
How dangerous are peroxides?
The stuff I have found.
If you distil an ether with no stabiliser and store it, they can be a big problem.
A bottle of 20 year old+ sec butanol from the peroxide test papers was off the scale.
If the stuff is the reactant it should not be a problem.
If the stuff is your solvent and you concentrate it with nothing that it can oxidise it could be a problem.
mick