Sciencemadness Discussion Board

looking for aniline in Canada

alexleyenda - 14-6-2014 at 12:08

Hi,
I'm looking for a small quantity of aniline in Canada, around 50-100 mL. Does anyone in Canada knows a source or have excess of it? It is very hard to find, and the only possibility I managed to find is 500 mL, which is way too much considering I only have 2 months left for home chemistry this year.

UnintentionalChaos - 14-6-2014 at 16:02

You can readily convert acetanilide into aniline in at least 80% yield of purified product. The former is a relatively nonhazardous solid and is probably easier to source and/or ship.

alexleyenda - 14-6-2014 at 16:20

That would require a simple reflux heating for 20-30 min in an NaOH solution right? I did not find any paper on it, as it is usually done the other way but I guess that should do the trick. However I looked at canadian chemicals supplyers... there are two who sells to individuals... none have it. Nothing interesting on ebay too.

UnintentionalChaos - 14-6-2014 at 16:36

Quote: Originally posted by alexleyenda  
That would require a simple reflux heating for 20-30 min in an NaOH solution right? I did not find any paper on it, as it is usually done the other way but I guess that should do the trick. However I looked at canadian chemicals supplyers... there are two who sells to individuals... none have it. Nothing interesting on ebay too.


Add something like 1.5eq of HCl to acetanilide and warm. This is just a paste of acetanilide crystals at room temp. It will all go into solution by the time it reaches reflux. Then, give it another 20-30min to finish hydrolyzing the last of the acetanilide. Add 2.6eq of NaOH solution (to account for the acetic acid the hydrolysis produces) and the aniline separates as a dark oil (upper phase). Seperate this from the salt solution, throw in some NaOH or KOH pellets and let it stand over them for a few hours to dry it, then distill, preferably at aspirator pressure to give clean aniline. Store in amber glass in a cool place to minimize discoloration with time.

Simple redistillation will remove the color should it turn a bit brown after sitting around for a year or three.

The problem with base hydrolysis of the acetanilide is that the produced aniline forms a separate phase which will extract the unreacted acetanilide into it and slow the hydrolysis unless you're stirring it into an emulsion. Also, anilines are far more stable as their acid salts and prolonged heating in base is only going to make extra tar and less product.

[Edited on 6-15-14 by UnintentionalChaos]