[RockinOnCola]

Hey there.

This part of a preparation that i'm following:

... in a mixture of methanol (18 ml) and water (2 ml), ABDV was added (75 mg).   After purging for 20min with argon, the mixture was stirred at 60C for 24h after which it was cooled down and the resulting co-polymer was precipitated into acetone. The solid was successively washed with acetone (200 ml x 3) and diethyl ether (200 ml x 2), centrifuged and dried under vacuum to give purified polymer.

I'm confused about the washing part.   The polymer needs to be dissolved in something so I can wash it with acetone doesn't it?   When it's in the separatory funnel I wash it with acetone and then discard the acetone?
Or does it mean i'm pouring acetone and diethyl ether over the solid polymer in vacuum funnel?

[Arkcon]

I'm confused about the washing part.

It seems so.

The polymer needs to be dissolved in something so I can wash it with acetone doesn't it?

 

Not always no.  Yes, in organic preps, we "wash" a product in solution with another liquid in a separatory funnel.  But if you dissolve a polymer, you may not get it back, or it may reprecipitate improperly, or something like that.

 

When it's in the separatory funnel I wash it with acetone and then discard the acetone?

Probably not this one.

Or does it mean i'm pouring acetone and diethyl ether over the solid polymer in vacuum funnel?

Probably this one.  We can also wash a precipitated compound.  The answer really depends on your next steps.

[wildfyr]

It means that after the material has been precipitated and filtered, the dried cake on top is rinsed with the other solvents while on a buchner funnel/filter flask setup.

I'm a bit confused about the centrifugation, and I assume that's what gets you too. The centrifugation should take place right after precipitation, or it could be a total typo.

Sometimes polymers precipitate as a very fine solid that will go right through a filter. This is when centrifugation is necessary. Washing can be done also by centrifuging, decanting the liquid, then adding the washing solvent, giving it a shake, then centrifuging down again.

[zarhym]

this is what I would do:

.. in a mixture of methanol (18 ml) and water (2 ml), ABDV was added (75 mg).   After purging for 20min with argon, the mixture was stirred at 60C for 24h after which it was cooled down and the resulting co-polymer was precipitated into acetone. Then the solvent was evaporated under reduced pressure. The crude solid was then triturated at XX°C in XX mL acetone for XX minutes. The filter cake was rinsed with XX mL acetone and XXmL EtOEt. The cake was then dried in oven at 30 to 50°C to afford pure polymer.

I am assuming your polymer has good particle size. If it is an amorphous solid, centrifuge and decantation should do the work.

[RockinOnCola]

It means that after the material has been precipitated and filtered, the dried cake on top is rinsed with the other solvents while on a buchner funnel/filter flask setup.

Thanks, i'll do this.