Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: valeg96 on 04/03/2014 11:10:49

Title: How do I produce quinine chlorhydrate from quinine?
Post by: valeg96 on 04/03/2014 11:10:49

I purchased some quinine bark in an old-timey drugstore, and I'd like to try and produce some quinine hydrochloride, the flavouring of tonic water. How do i proceed? Even a really basic method, it's just to try and get something. Is it enough if i pulverize the bark, let the alkaloid react in very dil HCl, filter and evaporate? I'm not going to eat it, I'd just like to have a fluorescent substance.

Title: Re: How do I produce quinine chlorhydrate from quinine?
Post by: chiralSPO on 04/03/2014 14:14:59

The HCl extraction should work, but I don't know how pure the material will be (there is not much quinine in the bark). It's it might be best to wash the dilute HCl extract with an organic solvent (imiscible in water) to remove some of the undesired material. After that, you could even make the quinine HCl solution basic (ammonium hydroxide is probably best) and extract the neutral quinine into a new portion organic solvent. Then extract that with dilute HCl to get the HCl salt back into water. This process will separate all the acidic and neutral impurities, but not necessarily remove other basic compounds.

Good luck!

PS: If the bark is too messy, you can also just try to extract it from tonic water (the type with sugar usually contains more quinine than the diet types)

Title: Re: How do I produce quinine chlorhydrate from quinine?
Post by: valeg96 on 08/03/2014 14:52:00

Thanks, how would you do it with the tonic water, and how much (approx) of it would I require? I think it may be troublesome to work with all that bark powder. Anyway I found a pyrex separation funnel, so the procedure is way easier now.

Title: Re: How do I produce quinine chlorhydrate from quinine?
Post by: chiralSPO on 09/03/2014 15:36:12

Different tonic waters have different amounts of quinine. I think most are around 50–75 mg per liter (diet tonic water is closer to 30 mg/L). Tonic water itself is highly fluorescent. Basification of tonic water with ammonia, and extraction with organic solvent (ethyl acetate is probably best) will yield the freebase. Or you can extract the solution of freebase quinine in ethyl acetate with dilute HCl to get the hydrochloride salt in the aqueous layer.