5449 problems again

[Ortist]

I read that phosphoric acid or mineral+organic acid mix give better yeld.
However I decided to try pure aqueous HCl hoping that I can get at least SOME yeld. Wanted to check if 5449 I bought is actually what it is.

So I heated up 20ml of water to 60 degrees, slowly disolved 10g of bmk glycidate sodium salt and slowly poured there 30ml of 35% HCl
with stirring.

In about 15 min white solid separated

In about next hour solid disappeared


Raised temp to 85 degreees and stirred for another hour.

Cooled down.

No layer separation.

After about 20min after cooling lots of crystalline solid separated in a flask, but not on the bottom , instead in whole volume.

Some phenylacetone smell, thats it, DCM extraction gave zero yeld.

Any thoughts?

 

[UWe9o12jkied91d]

Do you have a reflux collumn installed? while heating this?
You migh have your product dissolved in acid excess? Have you tried quenching or washing with salt water?

 

[Ortist]

Yes, with condenser. No quenching, extracted with DCM, washed with water, ecaporated DCM. Everyone says it must be bubbles during rxn but i didn't see any

 

[Ortist]

I tried to dissolve powder in cold water, then added some amount of H2SO4 conc. and brown oil immediately separated on the top. Is this normal behaviour for 5449?

 

[OrgUnikum]

Yes. Thats actually completely normal for most organic material to get burned by concentrated H2SO4 which is a powerful oxidizer (try adding it to sugar for instant fire).

Extraction is better done with a solvent with less density then water as the P2P will be on top after the reaction. Density water = 1, density P2P = 1,02. As the water is loaded with acids and salt the water layer gets denser (heavier) then P2P and so its on top. Extracting with a bottom puller (DCM) is just far from perfect - obviously.

 

[Ortist]

So the question is: when I dissolve 5449 in a water , then add H2SO4 I have immediate layer separation. The oil stays on top. Is this p2p? Or it is a glycidic acid? It doesn't smell p2p. Do I need to heat it & mix ffor decarboxylation?

 

[Ortist]

Another experiment was done on 10g of powder:

Dissolved in a hot water, heated & stirred fro 3 hours at 90 degrees with HCl.

Got 2ml of very viscous oil with smell of phenylacetone. This viscousity is from unreacted glycidic acid or polymerization?

 

[Ortist]

Can anyone check their 5449 pH (water solution) please? Mine is strongly alkaline. Is this normal?

 

[Ortist]

Another experiment, 80ml water, 10g sulphuric acid, 20g powder, 2ml P2P.
It makes me mad.

 

[Ortist]

After extraction added sodium bicarbonate to acid/water mix and it solidified. Unreacted glycidic acid? Never thought such a simple reaction can be such a mess. I made a mistake in a post above: it was 20g of H2SO4

 

[OrgUnikum]

More water. A lot more hot water to get all salts to dissolve. I suppose you did not use enough acid and you did not stir well enough. You would need twice the amount of acid and it should be used NOT as concentrated but at most as battery acid 38% and you would need about 60 g of this, then you get more water into the reaction too. Take your conc. H2SO4 20 g and add this to 50 g of water. Let it cool down in the fridge. Use this cold diluted acid.

Salvage:
To what you got last, when you used 10g H2SO4. you add 10 to 15 g conc. H2SO4 which was DILUTED with 60 to 90 ml of water and cooled down to roomtem-perature or less and the you reheat to 90 °C for an hour. That will do I say.

PS: As you seem not to be able or willing to follow simple instructions I have but little hope for any followup reactions, sorry, I do not want to sound mean, but it is pretty obvious.
This said I am out.

 

[Ortist]

oh, I made a mistake. I mean 80ml of water + 20g of sulphuric. This was added to powder which was dissolved in 30ml of warm water. Stirred in 250ml flask on a magnetic stirrer, 1500rpm, temp of the oil bath was 70 degrees.

 

[Ortist]

Last experiment with sulphuric acid, I stop playing with it, too upsetting :

1. 20g of powder was dissolved in 30ml of water with stirring
2. 25g of sulphuric acid 98% was dissolved in 40ml of water and cooled to room temperature

While stirring at 1500rpm acid was slowly added to glycidic acid salt, immediately it turned milky-white, with lots of tiny bubbles

After all acid was added stirring was stopped and flask taken from the stirrer for examination

Two layers formed: lower water/acid crystal clear and upper transparent oily layer.

Flask was returned to stirring/heating and was heated to 70 degrees and stirred. After about 3 min it turned milky white and was heated & stirred for 70 min.

After that RM was poured to small beaker to see if layers will separate.

On cooling layers separated: upper light yellow with smell of phenylacetone and lower milky white.

Addition of toluene resulted in fucking 3 layers. With some good stirring I was able to dissolve most of yellow oil in toluene but not all of it.

 

[Ortist]

Does anyone have a pic of how decarb. bubbling should look like?

 

[Ortist]

Aha .

Looks like my failures were all related to incomplete decarboxylation reaction. Which may be caused by insufficient stirring and/or reaction time. This time I got 40ml of crude p2p from 100g of powder (just top layer collected). Then I extracted water layer with DCM twice and added this to crude p2p and started washing with water.

Suddenly 3 layers separated: water, dcm and something else. This strange layer (20ml) was collected and treated with sodium bicarbonate. Lots of CO2 evolved and some tiny crystalls appeared on a surface. Liquid became water-soluble. To this some H2SO4 was added and immediately layers separated and I ended up with glycidic acid again.

So my guess I got 20ml unreacted glycidic acid at the end plus probably some amount of it in crude p2p.

Next experiment will do with mineral+organic acid mix for prolonged time, will post updates here

 

[Ortist]

40ml crude P2P yelded 2..3ml of P2P. . 100g of powder yelded 3ml. Ok enough of HCl experiments, lets try phosphoric and then dump all that 5449 I got to the drain. Never thought it can be so annoying.

 

[Ortist]

So far:

1. HCl only 37% + water solution of 5449: no decarboxylation visible up to reflux, zero yeld, just some phenylacetone smell

2. H2SO4 30% + water solution of 5449 : very low yeld

3. HCl 37% + oxalic acid + + water solution of 5449 : no decarboxylation reaction up to 85 degrees, zero yeld

4. H3PO4 85% + dry powder 5449 : visible decarboxylation starts at 60 degrees, yeld was not mesasured but it is higher than H2SO4