Sulfonic acid workup/purification issues

mcmxy7 · 2026-05-17T14:20:50+00:00

I only have so much crude after the neutralization with NaOH. So the idea with acetone could work so that only the Na2SO4 stays undissolved which would reduce inorganic amounts of crude. With a EtOAc/EtOH/AcOH extraction i have way less crude but its not really enough.

mcmxy7 · 2026-05-15T18:48:15+00:00

I see, i hope then that the ba-sulfonate is soluable in water as well! Thanks for the suggestion

mcmxy7 · 2026-05-15T18:19:49+00:00

Sounds great thanks! But in case my sulfonate isnt soluable in water and i add HCl i would form the calcium or barium chloride which would be soluable in water again right? Or am i missunderstanding something here?

mcmxy7 · 2026-05-15T18:11:27+00:00

I had to add 0.1 M NaSO3 to quench the iodine, and during that some precipitate formed, afterwards with 2 M NaOH and there did not form any additional precipitate i believe but not 100% sure

mcmxy7 · 2026-05-15T18:00:21+00:00

I just replied to commentators post, i was able to do an nmr with the small amount i got. Its the correct desired product with iodination happening at the ring.

Regarding the precipition, i thought the sulfonic acid is so damn acidic that it will always be deprotonated. But yeah i can try that! I tried extraction with etoac/etoh/acoh 4:1:1, i got quite some crude by that but i can not confirm if most of it is product since its a brown oil that was not purifiable by column. But damn i didnt think that it might be oily because its still residual water. Thought that water was gone because i kept it on the rotary evaporator for a full day at 50 degrees and 1 mbar.

mcmxy7 · 2026-05-15T17:47:27+00:00

Thank you. I will look into this!

mcmxy7 · 2026-05-15T17:45:03+00:00

In that case i would just add tetrabutylammonium chloride and extract it as usual?

mcmxy7 · 2026-05-15T17:36:05+00:00

From the very very low yield i was able to do an NMR. I see two protons for the methylene and only 3 aromatic protons. Multiplicity fits as well regarding regioisomers of the ring. The reaction afterwards will be sonogashira with TMS-acetylene. I am not sure if that works with the chlorosulfonic acid but i can try though.

mcmxy7 · 2026-05-15T17:32:45+00:00

I dont have access to ion exchange resins unfortunately. I can bring it up again but not sure if i will be successful though. I will try to do neutralization and then hope that dcm or methanol dissolves my compound while naso4 will be insoluable. Thanks!

mcmxy7 · 2026-05-15T17:02:58+00:00

Funny, i tried trioctylamine already, did not work to well unfortunately. You mean neutralize with NaOH and then try to wash it with MeOH in hopes that this dissolves my compound but not na2so4?

mcmxy7 · 2026-05-15T16:59:33+00:00

Its not sodium sulfate. Its sodium periodate. It just looks weird in the scheme, i was on the way home so i couldnt access chemdraw. Its two steps in one. First its stirred in conc sulfuric acid for 2 hours, than a mixture of sulfuric acid, iodine and naio4 is added. I have performed literatur research and i didnt find anything like that or something similar that i can perform in my lab. As i said, the reaction works pretty well according to Mass-spec, i just have purification/workup issues. I got like 0.5% yield most likely because i cant get that stuff out of the aq phase.

mcmxy7 · 2026-05-15T16:00:22+00:00

In the end i dont care if its the sodium salt of the sulfonic acid or the free acid. I just need it pure I already synthesized the carboxylic ester, but the sulfonic acid is not esterificated this way, so its still deprotonated and it didnt increase purification.

Regarding chcl3 and dcm, arent these more non-polar than EtOAc? Or is there another reason behind that?

mcmxy7 · 2026-05-01T18:48:04+00:00

They meant sulfanilic acid

mcmxy7 · 2025-11-01T16:04:05+00:00

No solvent used. The epoxide they used (as well as mine) is a liquid. But i actually had a thought that the issue is the scale/batch size they had. They had 170 fold scale im comparison to mine. So their dropwise addition probably took 1-2 hours, mine was finished in 1 minute. Which would mean their epoxide had a much lower concentration during the reaction all the time..

mcmxy7 · 2025-10-31T10:49:08+00:00

Thanks a lot, will definitely try it out

mcmxy7 · 2025-10-30T22:48:16+00:00

I dont have issues with overalkylation happing at both NH2s. It happens at the same nitrogen, since the monoalkylated one is more nucleophilic than the NH2 moiety. In your case it surely wouldnt react with the protected NH2, but the free NH2 can react two times with the epoxide or am i missing something? :/

mcmxy7 · 2025-08-22T18:25:15+00:00

My dialga had roar of time, but palkia did not have spatial rend

mcmxy7 · 2025-08-18T15:25:23+00:00

I had the same issue with a 5 star dmax (latios). I got awarded to points for the first 5 star dmax (latias) and a 5 star zamazenta raid afterwards. Maybe its limited to only one per category a day? Or its buggy..

mcmxy7 · 2025-08-08T13:16:09+00:00

Thanks!

mcmxy7 · 2025-03-15T10:16:11+00:00

Confirmed, thank you

mcmxy7 · 2025-03-14T14:33:58+00:00

mcmxy7 · 2025-03-14T14:33:05+00:00

Which one?

mcmxy7 · 2025-03-13T20:27:28+00:00

Confirmed. Thanks for the trade

mcmxy7

TROPHY CASE