Phenylacetone (P2P) synthesis from benzaldehyde with butanone

[Fenster]

Ok, step 3 - I added NaOH solution heated to 50c and put into mag Stir after 6 hours a thick almost solid creamy mess was in my rbf. I added DCM and two layers appeared. At first, I was very happy!!! As the creamy thick layer sat on the bottom and I thought the clearer layer was the DCM extracted goodies was on top. No no no..... The Milky thick layer was the DCM. I know for a fact that when I remove the DCM I'm not going to have a yellow clear oil aka p2p.


@HEISENBERG

Have you team reviewed this process before publishing. Seems the experts have gone silent on this proceedures. Would be nice to get some support on a method your team published.

Ok, so I'll attempt Distillation on the creamy mess and see what comes over.

 

[TheNut22]

Just use my own method, that is: Heat MEK and benz, with hydrochloric acid: 90-110 C, 3-5 hours.
Then put 10% KOH-solution in, and crystals appear immediately. Get rid of the water. Put them in freezer. Get rid of the oil. Pure, white crystals. ...you're wellcome!

 

[Cbison]

I already have the MPB solution and would like to get the crystals without distillation. The adol condensation was done through acid gassing. Do you think if acid is introduced in the Benz + MEK solution through gassing and heated up to 90-110°C for 3-5 hrs and washed with hcl before adding 10% KoH, is there a possibility of crystals precipitate immediately? Is it important to freeze solution to get crystals and what are your reagent measurements.

 

[TheNut22]

OH my god. DONT wash with acid, OK. Same amount of water that you used acid.

 

[G.Patton]

You ask about method review but you don't follow the method and complaining that something went wrong
DCM is non-polar solvent, chloroform is polar solvent.

 

[Fenster]

D
DCM has a dipole moment. It is polar albeit slightly.

Are you sure your a chemist? I don't mean to be rude but DCM is not an NPS in the traditional sense.

Can I ask, have you or your team performed this method in totality?

 

[TheNut22]

I use little bit of ethyl acetate (dipole almost same as DCM) and xylene, and it works like a charm.

 

[Fenster]

What I need help with is the step 2.

I have 50% H2O2 and GAA. The amounts in the write up are 10L of GAA and 1300g of H2O2.

Are they expecting me to weigh the 50% H2O2 or am I supposed to accept it as a typo and use 1300ml?

The other write up is using sodium percarbonate directly and this write up here is generating it in situ. With GAA and H202.

I just need to confirm the amounts listed.

 

[Fenster]

50% H2O2 = 1.197g/ml

1300g h202 (50%) = 1086ml

10:1 GAA to H2O2 to make acid in situ.

Is this the amount or is it a typo?

This process is being completed with lab grade reagents and glassware so if I follow it directly I should get the same results. However this write up needs work. Let's get this corrected and published as it should be.

 

[Fenster]

Here is the original forensics work up from the twodogs proceedures. Obviously it varies a little from the OP here as the method here makes sodium perborate in situ. I'm just trying to make sense of the ratios.

 

[G.Patton]

It sounds rude. Do you know forum rules? You are right, i was wrong about DCM, I thought it vice versa. And yes, I am chemist actually but don't want to answer you any more.

solvent and relative polarity:
hexane 0.009
chloroform 0.259
methylene chloride 0.309
acetic acid 0.648

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[Fenster]

Ok, thanks.

Do we have a definitive answer though. Has this been tested and developed in house or is this method scraped from somewhere else?

 

[TotalSynthesis]

@Fenster actually i dont even understand your problem but it seems you dont even understand what will be "generated in situ"

what you need is peracetic acid and this can be generated in situ by adding sodiumperborate to acetic acid,

second way is by mixing h2o2 with acetic acid and a tiny little bit h2so4. this is best to let it sit for a few days.

this method works, i tried it myself. Dont ask me for my exact h2o2:GAA ratio because mine again was a bit different and i only used 35%h2o2

only because of varied quantities of whatever it does not mean that one way does not work but the other does.
if you understand what's happening, then you'll be able to do small adjustments but if you dont understand whats happening then better do not claim a method to be bullshit

 

[Fenster]

Sodium Perborate is insanely cheap and easy to acquire so why use Peroxide at all?

 

[Felix34-73]

2) The solvent is evaporated under vacuum. 2-Acetoxy-1-phenyl-1-propene (cas 24175-87-9) 800 g how many degrees and how many mm hg pressure here
-------------------------------------------------
3) evaporated under vacuum. 1-Phenyl-2-propanone yield 650 g. how many degrees is this how many mm hg pressure

 

[Fenster]

2) There isn't much information about this compound. I got a yellow oil after the DCM stopped coming over.

3) there is a lot of tar as a side product. I couldn't concentrate the vapour enough to get enough vapour to distill even under vacuum. I'm going to run this through on a larger scale then I did (I ran 100g of Benzaldehyde through) if I still have trouble getting the P2P to come over I'm going to steam distill everything including the DCM, the p2p should come over with the h20 and dissolve straight into the DCM where it can be separated. Like a an essential oil Distillation.

 

[jokerr]

Will you do the synthesis video of the formula?

 

[Felix34-73]

For the pH neutral process, I will use sodium carbonate + how many Gr, I will make the pH in the separating funnel neutral, I can make the scarbonate and water mixture directly in the solution and bring it to pH 7 level.

 

[jokerr]

hello masters,
I started from the first stage.
I added 100 g of benzaldehyde and 100 ml of mek, cooled it to 0 degrees and gassed for 1.5 hours.
then I stirred it for another 1.5 hours at room temperature and it will rest overnight.
continue operations tomorrow.

 

[Fenster]

Im running the same process at the same stage. Don't expectuch help from the team here. They seem to have abandoned this write up. I think a lot of write ups are just copy pasted.



Consider, that MEK and Benzaldehyde have different molecular weight and density. Therefore 100ml of MEK is not 100g. This only an issue later when you go to add 100g of h202(50%)

There are several measures in this write up where one side of the reaction is stated in grams and the other in MLS. H2O2 I stated in grams of a 50/50 mixture. So you have to account for the water and the peroxide when calculating the MLS from weight. Unless your going to start weighing liquids.

Let me know how you go, when I did .1M reaction I ended up with such poor yields that i couldn't extract the p2p from the tar crap. This write up doesn't really inform you much along the way of what to expect. You can the impression of just extract and distill.

Let me know how you go extracting the MPB tomorrow. Did your Rx mixture go bright red?

 

[Ortist]

This writeup contains a few serious mistakes thats why. In particular the last step is completely wrong. Doing it as describet you'll end up with tar and a few % of p2p

 

[Fenster]

There is the possibility of steam distillation of the product. You will see what I mean by tar when you get to the extraction. Are you using chloroform or DCM?

 

[TheNut22]

I don't understand, why you don't use different solutes for extraction. Just look how the molecule will dissolve to different solutes, and choose the solution that works best for you. Smh ..

 

[jokerr]

hello master.
@G.Patton
The solution is extracted with chloroform (CHCl3) 800 ml x2, then the extract is washed with sodium bicarbonate solution (NaHCO3) to neutral pH

Are there two different operations in order of what I need to do in this section?

liquid / liquid extraction
acid /base extraction.

do i understand right? .

 

[jokerr]

Hello ,
I use chloroform.
I got a dark yellow form.

 

[jokerr]

my calculation is like this, where am i doing wrong? can you please explain.

100ml benzaldehyde 100ml methyl ethyl ketone
hcl 40gr salt and 15ml sulfuric acid
200ml pure water
chlorform 80+80

sodium bicarbonate 10%- water 90%