Ethyl Acetate MHRB extraction

[awalmartbag]

I wanted to try extracting some MHRB with ethyl acetate.

When I did an extraction with heptane, I basified the acidic aqueous solution directly in the separatory funnel after de-fatting.

I assume I should not do this with ethyl acetate, because hydroxide will break it down into acetate and ethanol, correct?

So I should extract MHRB with acid, defat, remove from funnel, basify, collect solids, wash to remove excess hydroxide, then dissolve in ethyl acetate and wash w/ water - correct?

 

[blig-blug]

I don't know about an extraction using sodium hydroxide, but I can recommend HIELO: Wiki - HIELO

 

[awalmartbag]

I should have been more clear, sorry. Basically, my idea is to do a Lextek-style A/B extraction, just using ethyl acetate instead of shellite

 

[Transform]

I'm not convinced you'll get an easily separable solid phase from adding sodium hydroxide to an acid MHRB cook. You could try bringing the tea to pH7 with the NaOH, then adding sodium carbonate to raise the pH further before trying the EA pulls. If you get them done quickly hydrolysis shouldn't be much of a problem.

It may also prove necessary to add a dash more Na₂CO₃ solution between pulls. Just bear in mind that what you're doing is mildly experimental, and have a look for existing literature where EA gets used as part of some other alkaloidal extraction.

 

[awalmartbag]

I did find an undergrad research paper where alkaloids are extracted with EA - these were harmalas from Rue, but the process was the same: acid cook, defat (here they used 1:1 EA and petroleum ether), basify (NaOH, no pH given), liquid-liquid extract (pure EA). The solid was not isolated in any intermediate step, only at the end.

I'll also try the honey tek blig-blug posted, but I'll try to turn it into freebase at the end (to calculate a moderately accurate oral dose)

 

[Transform]

I did find an undergrad research paper where alkaloids are extracted with EA - these were harmalas from Rue, but the process was the same: acid cook, defat (here they used 1:1 EA and petroleum ether), basify (NaOH, no pH given), liquid-liquid extract (pure EA). The solid was not isolated in any intermediate step, only at the end.

I'll also try the honey tek blig-blug posted, but I'll try to turn it into freebase at the end (to calculate a moderately accurate oral dose)

Can you link to a copy of the paper? If they added NaOH to rue harmalas it'd be exceedingly difficult to avoid getting a precipitate once the pKₐ of the harmalas get met. It would be good to see what they had to say about that.

 

[awalmartbag]

Here it is

They just leave the solid precipitate in the separatory funnel and shake it after adding EA, seems like