Sciencemadness Discussion Board

Epoxide reduction

(Brain)2NH - 27-7-2013 at 07:31

Hi,

I have access to a considerable source of scopolamine (around 10 gr)
I'm thinking of the following series of reactions to make tropine.

my question is how to get rid of that epoxide, after hydrolysis ?
there's a hydroxyl group there, if matters.

TnX


Scoppolamine.JPG - 34kB tropine.JPG - 17kB

zed - 27-7-2013 at 15:23

Might be easier to make Tropinone outright from simple building blocks, then reduce it to Tropine.

http://en.wikipedia.org/wiki/Tropinone


kch - 2-8-2013 at 07:17

It's going to be very difficult to do this for two reasons. First, you have to protect your existing hydroxyl group. Next, your best product from the epoxide is basically going to be a glycol. That isn't really feasible to work with if you don't have a hydrogenator or an equivalent setup.

Mercedesbenzene - 2-8-2013 at 12:02

I didn't find any papers on what you are trying to do, but by looking at it I can make a hypothesis on what might work. First I would hit scopolamine with NaBH4. This should eliminate the epoxide leaving an alcohol and it is not powerful enough to reduce the ester.

The next step is to take the alcohol to an alkane. The best method here might be to use tosyl chloride then sodium borohydride again.

Finally cleave the ester with base.

This might give you tropine. Best way to find out is to try it!