cryomancer
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Use for a reagent
Does anyone out there know of a use for p-toluenesulfonic acid that does not require any fancy glassware. Just basic
beakers for the most part, i really dont own much at all(still in high school here, limited funds)
Now the reason i even have this reagent is because I wanted to preform the reaction by UC235 here: https://www.youtube.com/watch?v=BBQqu28ly-k
At the time I was a Junior in high school but the science department was pretty equipped and i knew the dpt head and
the other chem teachers. So i joined our "science club" (it hurts to even remember that laughing stock of a thing) and i suggested the reaction and
they said all right lets do it. So i got it cleared but all the people but make a long story short it fizzled and it never occurred, but before it did
I was busy trying to acquire the previously mentioned reagent and found it to be quite expensive, so I had a connection that you all may know or have
heard of: Derek Lowe (yes the blogger and medicinal chemist Derek Lowe) and i asked if he would send me a small 2g sample of the reagent and he
did.
So now i have 2g of p-toluenesulfonic acid just sitting around. If you guys cant figure something out im just going
to give it to my AP Chem teacher.
I know it was 90% story 10% question but i like telling stories to people
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j_sum1
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No idea about the p-toluenesulfonic acid.
How is it you know Derek Lowe? (Thanks for the story.)
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Cryolite.
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p-TSA is a generically useful reagent: it is a strong acid, like sulfuric acid, but lacks any of the oxidizing properties of sulfuric acid: when added
to an iodide salt there is no oxidation to iodine. It is also soluble in toluene, meaning that it is a good acid catalyst for reactions which produce
water like esterifications and acetalizations: the water can be azeotropically removed with a Dean Stark.
It is extremely hygroscopic, though (worse than KOH) so storing it will be a difficult task.
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Muffin Man
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All I'm gonna say is:
There is a 90% conversion of Δ1→Δ6 THC if p-toluenesulfonic acid in toluene is used during isomerization.
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cryomancer
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How I know him is through my mother who went to Hendrix Collage with him and several other people of mention so she
was my connection to him
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cryomancer
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Quote: Originally posted by Cryolite.  | p-TSA is a generically useful reagent: it is a strong acid, like sulfuric acid, but lacks any of the oxidizing properties of sulfuric acid: when added
to an iodide salt there is no oxidation to iodine. It is also soluble in toluene, meaning that it is a good acid catalyst for reactions which produce
water like esterifications and acetalizations: the water can be azeotropically removed with a Dean Stark.
It is extremely hygroscopic, though (worse than KOH) so storing it will be a difficult task. |
Right thats the what it was to be used for in the ketalization reaction, but a huge hang up is we didnt have a Dean
stark strap. Come on what half decent lab doesnt have a dean stark trap even if its a high school lab
The acid is extreamly hard to dry and that is why i have not even opened the vial it came in and it still looks like
it had absorbed a small ammount of moisture as there is a light coating on the sides of the vial
[Edited on 17-8-2016 by cryomancer]
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Cryolite.
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You should probably be storing that toluenesulfonic acid in a dessicator if you want to eventually use it someday. This isn't too difficult to setup:
take a tightly sealable flat bottom container, pour some sodium hydroxide granules on the bottom, and then place the vial gently on top.
Also, dean stark traps are sold on ebay for relatively cheap nowadays. Here is one for about 10 dollars. http://www.ebay.co.uk/itm/381569370564?_trksid=p2057872.m274... I purchased one of these and it works pretty well as a trap if you fill the
collecting part of the flask partway with toluene: the amount of solvent needed to start collecting otherwise is a little bit too much for my tastes.
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cryomancer
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@Cryolite
Well i never really checked Ebay for glassware. But you know School regulations, but our plan was to borrow one from
the local collage that is run by the same organization that runs the high school (private school for the win) but it never happened
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CharlieA
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I ordered a Dean-Stark trap from ebay, like the one referenced above. It arrived broken at the top of the side-arm. The packaging was generally good,
but the glassware is susceptible to "twisting" and the packaging did not protect against that. A glass rod from the reservoir to just above the ST
side-arm$10joint would be a great help. Dean-Stark traps constructed with the reinforcing arm are considerable more then $10. I don't have any
complaints with the vendor as it refunded my money promptly.
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