Phenylacetone (P2P) synthesis from benzaldehyde with butanone

[a_king]

is it possible to replace chloroform?

 

[Waspamine]

yh I know 2 yrs late but yh, so chloroform is really easy to synth, look up some on ytb you'll see

 

[MadHatter]

I guess what I'm really wondering about is the stochiometry of this reaction. In other write-ups of the bayer-williger I can't seem to find this enormous amounts of GAA. Can somebody help me with the rationale? I'm really close to trying this one out, but the amount of GAA is problematic.

 

[ByHyde]

I've been working on this synthesis for a long time. I work with sodium perborate and synthesize sodium perborate myself. And break it into pieces, spreading the oxidation over 12 hours.
1 GR MPT= 3.5 ML GAA +2.5 GR PSB+2 ML ACETONE I hope good days are near.

 

[billythekid]

this amount of gaa is a lot and my best guess as to why is that preparing Peracetic acid in situ (during the reaction) and without a catalyst is inefficient so the chemist overcompensates to help with this, also GAA is used here as the solvent
by making the peracetic acid days before and testing the available oxygen content you are likely to get better results. This being said, I have seen professionals use this method and only get at best 35 to 65% of finished product. so an inexperienced chemist is likely to get even worse and a newbee is likely to fail or even worse hurt themselves. I recommend reading and studying and start small
make sure you thoroughly clean your finished reaction mix at the end of each step, Do not exceed -5c in the aldol condensation let mek/benzaldehyde stir overnight in the fridge after gassing.
do not exceed 60c in the Bayer villager. and research other oxidizers because I get better results with a different one.

 

[TheNut22]

But I have a question. Again. Because I'm also learning, and this is, I think 23 to 24:th attempt!
So, the question is: Now I'm doing the base hydrolyzation of acetoxyphenylpropene to P2P.
The solution must be neutralized when the hydrolyzation is over. I'm out of GAA. Can I use my formic acid to neutralize the soluition, or even hydrochloric acid?

 

[lalalander]

I'll synthesize oxone by neutralizing Caro's acid. But DMF has to be used as solvent, which is very expensive in my country. Maybe I can follow the peracid method you mentioned.

 

[lalalander]

You don't need to use glacial acetic acid. You can use white vinegar from the supermarket.

 

[TheNut22]

It worked, I neutralized it with formic acid. Now I'm distilling the ethyl acetate from ethyl acetate/P2P-mixture.
Then I will purify it and extract it again with ethyl acetate, because I can distill with atmosf pressure the ethyl acetate away again, leaving my P2P in the flask.

 

[TheNut22]

My acetoxyphenylpropene was perfectly clean, even when I tried to wash it with water, no dirt came off. The yield was also the best so far. It is really worth making the peracetic acid separately and letting it brew for 3 days before use.

 

[TheNut22]

Do you think that P2P is then pure enough to perform Leuckart reaction?

 

[lalalander]

If you can't distill it but P2P looks as clear as sunflower oil, I see no reason not to try it.

 

[TheNut22]

I noticed, that my P2P is not soluble in ethyl acetate, but in xylene. So, this is the first time that I really made acetoxy and P2P. Now my P2P is in xylene. Xylenes has boiling point around: 138-140 C. So, if I distill those xylenes from my P2P solution in atmospheric pressure. I will try the Leuckart-reaction. I was wondering why my Leuckart didn't work, so there lies the answer. I didn't have even P2P those last times.

 

[ZMI_AA0B]

Teacher, how can I achieve such a vacuum degree

 

[ZMI_AA0B]

Teacher, if you don't want to do so much and want to shorten it to one-fifth, can you still succeed? It means the materials are all reduced to one-fifth

 

[TheNut22]

I have washed my P2P 2 times, and it is still red coloured when all of it (~20 ml) it sits in my measuring flask.
When it was in my pyrex dish, it was clear coloured, and when it was stuck in the instrument I was taking it out it was yellow coloured.
Is this normal? It is in oil form, and the smell is very honey-like.

 

[ZMI_AA0B]

When I introduce hydrogen chloride, it also turns red

 

[TheNut22]

When I re-watched the P2P steam distillation video in here. I noticed the impure P2P looks exactly like mine. So, I just have to distill it, because I don't want to fail in the Leuckart-reaction, because this MEK + benzaldehyde to P2P is a lot of work. A LOT. I'm going to distill it at normal atmospheric pressure. I've noticed many chemists in one popular forum talking they've distilled P2P in normal pressure, without any problems. Uncle Fester, who's books I read, says it will decompose, but it is time to try it.

 

[TheNut22]

I didn't distill my P2P, because with last washing (3 washings) I was left 3.6 g of P2P.
It was as clear that you could definitely see the bottom of the flask, like there was red colored water in the flask. But it was of course without any water, and solutes.
It was very thick oil, but I dropped it with formamide, and catalysts with my pipette inside my boiling flask in about an hour. The reaction looks good now.

 

[TheNut22]

From now on I will further discuss my Leuckart in appropriate forum. If I fail, or got anything new to share with you with this synthesis, my dear community here, I'll be back.

 

[WillD]

Think about adding water before starting the process.

 

[WillD]

For distillation P2P without a vacuum, you need to use steam

 

[WillD]

This is normal, the fact that it becomes red. With recrystallization with ethanol, this can be purified

 

[TheNut22]

Adding water to Leuckart? No. Or why?

 

[TheNut22]

I have gradually heated now for about 5 hours. My reaction temperature has been 160 C now for about 3 hours (my digi-meter is outside the flask). I'm ready for 24 hour reaction, but what do you think, how many hours should I heat this. I have AlCl3 catalyst, formamide, my P2P and formic acid in there with boiling stones.