Sciencemadness Discussion Board

Dithionite Reductions

innervision - 25-8-2015 at 02:33

I see a lot of talk in various places online of using sodium dithionite for reducing nitro compounds, but a lack of details; especially in the solvents used.

If I were to reduce nitrobenzene to aniline with dithionite, how would I do it? I remember seeing ~3-5 eq. dithionite being needed, while browsing google images for dithionite reactions.

Say I had 10g nitrobenzene and used 31g sodium dithionite (3x molar eq.), How much solvent (MeOH:H2O) would be needed for the reflux?

byko3y - 25-8-2015 at 04:31

innervision - 26-8-2015 at 03:41

The reductions to luminol have been the most helpful I've found for giving me a general idea.

What determines why they used 200ml water? Is it just whatever is necessary to boil smoothly?

In the case of a nitroaromatic, is the MeOH:H20 miscible with it in the proper ratio, and the amount of solvent determines how much dithionite is dissolved, affecting the rate of reduction?