Sciencemadness Discussion Board

Cheap replacement for tetraethylammonium

DraconicAcid - 12-12-2017 at 21:19

So there's a couple of compounds I'd like to make with the tetraethylammonium ion- a nice, big cation that precipitates and stabilizes lots of large complex anions. Tetraethylammonum salts are a bit pricey, though, although cheaper than tetramethylammonium ones. Choline chloride is cheap as all get out, but the hydroxyl group can coordinate to metals and muck up the chemistry.

Acetylcholine chloride may work better, but I hesitate to work with things that are so physiologically active.

Can anyone think of a cheap substitute?

clearly_not_atara - 12-12-2017 at 21:39

On Sigma at least tetraethylammonium bromide is significantly cheaper than the chloride. You can also get benzyl chloride and triethylamine and make your own triethylbenzylammonium chloride by rxn in acetone generating a precipitate. Triethylbenzylammonium is a PTC though so I don't know if it will precipitate with what you want it to.

DraconicAcid - 12-12-2017 at 21:45

PTC? Pretty thick cation?

I wonder if the hydroxyl on choline is nucleophilic enough to make an ester with benzyl chloride....

TEA bromide would be great for making bromo complexes, but bromide tends to be a pretty good ligand, so it wouldn't work for making other complexes.

Chlorocholine chloride doesn't have the hydroxyl, but is expensive.....

[Edited on 13-12-2017 by DraconicAcid]

Sigmatropic - 12-12-2017 at 22:07

"Acetylcholine chloride may work better, but I hesitate to work with things that are so physiologically active" I highly doubt that considering the presence of numerous esterases especially present in the gastrointestinal tract, liver and blood.
http://howmed.net/pharmacology/acetylcholine/
I would be alot more worried about the neurological effects of tetraethylammonium. Have you considered tetrabutylammonium salts? They don't strike me as expensive.
https://www.amazon.com/gp/aw/s/ref=is_s?k=Tetrabutylammonium...

[Edited on 13-12-2017 by Sigmatropic]

DraconicAcid - 12-12-2017 at 22:18

Quote: Originally posted by Sigmatropic  
"Acetylcholine chloride may work better, but I hesitate to work with things that are so physiologically active" I highly doubt that considering the presence of numerous esterases especially present in the gastrointestinal tract, liver and blood.


Biology and biochemistry aren't my strong points. I just vaguely remember it being part of the nervous system.

Quote:
Have you considered tetrabutylammonium salts? They don't strike me as expensive.
https://www.amazon.com/gp/aw/s/ref=is_s?k=Tetrabutylammonium...


They are expensive on Sigma-Aldrich, which is where I was checking prices. Your link doesn't ship to Canada, but I'll check other places.

ETA: Benzyltrimethylammonium chloride seems to be nicely cheap.

[Edited on 13-12-2017 by DraconicAcid]