Sciencemadness Discussion Board

Determining completion of Bamberger rearrangement

thors.lab - 4-1-2020 at 21:24

Hi,

I will be performing the Bamberger rearrangement as per this procedure..

The procedure calls for the use of a dichromate solution to determine whether the reaction has completed. Oxidation of p-aminophenol yields some quinone imine (side note, not sure how to name this compound. Care to shed light? O=Ph=NH), while oxidation of the phenylhydroxylamine will of course yield nitrosobenzene. The procedure then says to smell the solution to determine the presence of the nitrosobenzene.

Of course I don't want to go around smelling nitrobenzene and nitrosobenzene. I also don't have any dichromate salts right now and would rather not have to buy them for this procedure. Additionally if I were to perform this on a smaller scale I would not want to waste product checking.

Does anybody have any alternative methods for gauging the completion of the Bamberger rearrangement?

Metacelsus - 5-1-2020 at 06:07

TLC would probably work. Check for disappearance of your starting material and formation of a new spot.