Syno conversion

[anunknownuser]

I tried my first syno conversion (to TNE) and everything was great until I added the NaOH.

I mixed the NaOH with water and then added it to the filtered syno solution. It started bubbling and turned yellow and a precipitate formed instantly. Did I add too much NaOH? If so how much NaOH should I add to a 5 cart (10 gram with one bottle heat) ? Do I need to disolve the NaOH in water first or just add it?

Thank you very much for your replies, I had to throw out my last batch, it was like a yellow soap.

 

[Alcibiades]

You do realize TNE is yellow, right?

I think the base turns yellow because of the deprotonated estradiol.

I use a NaOH solution to extract the estradiol after hydrolyzing the benzoate ester with NaOMe when I make TP and the base extract is a bright yellow.

You have solubility issues if you use too much water since neither steriod is water soluble .... the precipitate was TNE and TP.

Hopefully you are using methanol as the solvent otherwise your test will hydrolyze very slow if at all, and dissolve as much hydroxide in the MeOH as you can then add only a small amount of water, say 3-5% to aid in dissolution.

A better choice of base is KOH which is more soluble in alcohols.

You guys seem to think that you add a base and POOF! your TP is instantly hydrolyzed, but that isn't the case. The proprionate ester is fairly stable under basic conditions and you may have to push on it to get it to react at a decent pace.

When I make TNE is use KOH in methanol with 3% water and reflux(boil) it for a couple hours to get the prop to cleave.

 

[anunknownuser]

Thanks for your reply!

I think in hindsight I used to high a concentration of NaOH. I probably disolved about 10 tablespoons in about 8 ounces of water. The precipitate was so soapy that it instanly coated the sides of the filter whenI attempted to filter it and the MeOH wouldn't even pass through. I have also learned to use smaller amount of source material at a time. 10G was too much to waste on an experiment.

Thanks