Sciencemadness Discussion Board

Benzalkonium chloride PTC?

harveyclayton - 15-7-2019 at 08:45

Just wondering what you thought about using benzalkonium chloride as a phase transfer catalyst?
It is alkylbenzyldimethylamine chloride, where the alkyl group can vary. Thus it should be fairly soluble in non-polar solvents, and could therefore be used as a PTC, for example when performing NS on haloalkanes.
It is found in many OTC algaecides.
That's all, what do you think?

ZetekitoxinAB - 4-8-2019 at 09:03

It seems plausible to try; how do you intend to do your NS? I would think the best yields would be obtained in anhydrous conditions; for example reflux a primary haloalkane with dry KCN in a polar anhydrous solvent (DMF, DMSO, absolute etanol) with 18 crown 6 as a catalyst.

The problem with Benzalkonium is that it is very hygroscopic and difficult to dry; isolating it pure from commercial products would also be troublesome.

ZetekitoxinAB - 4-8-2019 at 09:08

I made a mistake in my post above; NS could easily be done between aqueous and organic layer using PTC; your best bet is to use a drop or two of a concentrated benzalkonium solution