the tosylation article you've all been waiting for

[psyloxy]

TsOH + MeOH + Fe³⁺-montmorillonite ^___DCE^___> TsOMe ; 80°C, 3h, yield: 82%

https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000505319-TET56_2000.djvu" target="_blank" title="Download this file">

Tetrahedron 56 (2000) 7291 - 7298

--psyloxy--
toluenesulphonate tosylate tosylation tosic ester

[Aurelius]

I remember a bunch of posts a while back concerning this, but am too lazy to look it up right now.

[ning]

Hmmm, I wonder too...what could a safe-to-handle, efficient, {kind of OTC} methylating agent bee good for? Hmmm.....

I guess nothing, unless one is in the habit of methylating syringaldehyde or hydroquinones...

Good find psyloxy!

(I wonder what the trick is?)

[ning]

with that 80 g or whatever of catalyst, I wonder how much mescaline could bee made?

psyloxy, I know you thought it was a bad idea, but I want to repeat here for all the bees that naphthalene can be sulfonated to produce "napsic" naphthalenesulfonic acid, which I bet could be substituted for tosic acid. IIRC, producing tosic acid requires either high temperatures or oleum. If there is interest, I can look it up again.

Too bad they need a 10 x excess of methanol. Probably it could bee recovered and reused.

I wonder if PTC could accelerate this reaction?

Well done! And here ning was going to make a methyl chloride generator!

[psyloxy]

10 times excess ? They used 4 equiv. of MeOH, which isn't even necessary as demonstrated by the reactions with higher alcohols: if one equivalent is used yield is only a few percent less.

--psyloxy--
PS:

Post 505622

(psyloxy: "H2SO4 + toluene --> p-tosic acid", Chemistry Discourse)

[ning]

You have been busy....I stand corrected.
If only halfapint were with us now....

[Nicodem]

producing tosic acid requires either high temperatures or oleum

I made some TsOH from 35% sulphuric acid by first concentrating it as much as possible by the ordinary method (boiling off water under vacuum) and then following the procedure as described in Organikum (reflux with a Dean-Stark trap).
Actually there is much more work to purify the product than to make it. Needles to say that the xylenesulphonic acid is even less demanding while equaly useful. It can't get more OTC than it already is.