Triflic Acid - 9-6-2022 at 23:18
As part of my vanillin synthesis, I plan to do alkali fusion of my p-TsOH to get p-cresol. Was wondering about how to safely do this. I have melted
sodium hydroxide before, but that was just to dissolve some glass to make sodium silicate. I'm also concerned about temperate control to prevent
decomposition. Additionally, all of my p-TsOH is in the form of the monohydrate. I'm concerned that the release of water vapor could cause the molten
hydroxide to bubble, which would be very bad to put it lightly. Any advice on how to stay alive and get a good yield is appreciated 
Tsjerk - 10-6-2022 at 00:28
Do you have toluene? You can dehydrated the TsOH by azeotropic distillation.
Triflic Acid - 10-6-2022 at 09:35
I do, that's how I made the TsOH. I also have a dean stark trap, so that shouldn't be too hard. But will I need to dehydrate the TsOH in order for
this to work?
UC235 - 10-6-2022 at 19:44
https://www.sciencemadness.org/whisper/viewthread.php?tid=11...
You might be better off preparing sodium tosylate. The naphtholsulfonic acid sodium salts can be recrystallized from 10% aqueous NaCl. No need to
neutralize. They will steal the sodium ions they need and crystallize out. Probably you can just dissolve the pTsOH in as little water as possible and
add brine then filter off the product.
Fusion is easier to do with 60:40 w:w KOH:NaOH which is a low melting eutectic. The molten hydroxide will spit somewhat. Heavy gloves/jacket/face
cover strongly recommended. Also IIRC, a LOT of SO2 is released when you dissolve and neutralize the product.
Further reading: https://www.sciencemadness.org/whisper/viewthread.php?tid=11...
[Edited on 11-6-2022 by UC235]
Triflic Acid - 10-6-2022 at 19:56
I'll do the neutralization, that's a stupidly simple idea that I'm disappointed I didn't think of doing. I'll probably do this tomorrow then, followed
by the alkali fusion. Will report as to how that goes.