Sciencemadness Discussion Board

benzyl chloride

ayhan - 27-6-2007 at 23:48

İs it available procedure for the preparation of benzyl chloride via benzyl alcohol and thionyl chloride? thanks...

evil_lurker - 28-6-2007 at 08:25

Thionyl chloride for making benzyl chloride? WTF?

Just take some benzyl alcohol, add an equal volume of muriatic acid, heat to 80ÂșC, then bubble HCl gas into the mix... you'll start gassing and gas some more then suddenly it will all turn cloudy in a matter of a few seconds, go homogenous, and then seperate.

Allow to cool and wash with sodium carbonate solution to neutralize any free acid, then distill.

Yields are 90%+.

garage chemist - 28-6-2007 at 10:07

If you use an excess of concentrated HCl, you dont even need to bubble in HCl gas.

guy - 28-6-2007 at 10:16

Can you make the HCl more "concentrated" by adding concentrated H2SO4? For example, if I wanted to make isopropyl chloride, can I use 30% HCl and some 96% H2SO4?

[Edited on 6/28/2007 by guy]

garage chemist - 28-6-2007 at 10:37

In the case of isopropyl chloride, no! The H2SO4 would strongly catalyze the elimination of water from isopropanol and leave you with propene.
Anhydrous zinc chloride must be used as the catalyst in this case, and concentrated HCl. 30% should work too, though, maybe with slightly lower yields.

guy - 28-6-2007 at 10:43

Ok I see. I could easily produce ZnCl2*hydrate but can I dry it will the H2SO4?

Edit: STupid question it would just form ZnSO4

[Edited on 6/28/2007 by guy]