Phenylacetone (P2P) synthesis from benzaldehyde with butanone

[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.

 

[billythekid]

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.

MadHatterthis 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]

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.

billythekidI have 50 grams of methylphenylbutenone. Is 300 ml:s (exept from 500 ml:s of GAA) of GAA enought to make peracetic acid in situ with 65 g of 50% H2O2? Because if I put that 500 ml:s, I think that is too much, like many says.
So, is that 300 ml:s of GAA enough?

 

[TheNut22]

I have 50 grams of methylphenylbutenone. Is 300 ml:s (exept from 500 ml:s of GAA) of GAA enought to make peracetic acid in situ with 65 g of 50% H2O2? Because if I put that 500 ml:s, I think that is too much, like many says.
So, is that 300 ml:s of GAA enough?

TheNut22It seems like it dissolved all, so I think 300 ml:s of GAA is enough. Thoughts?

 

[TheNut22]

I have 50 grams of methylphenylbutenone. Is 300 ml:s (exept from 500 ml:s of GAA) of GAA enought to make peracetic acid in situ with 65 g of 50% H2O2? Because if I put that 500 ml:s, I think that is too much, like many says.
So, is that 300 ml:s of GAA enough?

TheNut22...Aaannd, I put 3 ml:s of ~75% sulfuric acid in there, and put the whole shebang together to my closet for at least 12 hours. Maybe around 24 hours, and then start heating it for 6 hours at temperatures: 50 - 55 C. Is this correct?

 

[billythekid]

I have 50 grams of methylphenylbutenone. Is 300 ml:s (exept from 500 ml:s of GAA) of GAA enought to make peracetic acid in situ with 65 g of 50% H2O2? Because if I put that 500 ml:s, I think that is too much, like many says.
So, is that 300 ml:s of GAA enough?

TheNut22you dissolved the mpb in the acetic acid already? or did you make the Per acetic first?

 

[billythekid]

you dissolved the mpb in the acetic acid already? or did you make the Per acetic first?

billythekidy i re read your response and it sounds good add the per acetic acid dropwise and dont let the reaction temperature goi above 55 c addition of the per acetic acid is going to be exothermic

 

[billythekid]

you dissolved the mpb in the acetic acid already? or did you make the Per acetic first?

billythekidyes thats alot of glacial acetic acid there should also be acetone in there too but with the extra acetic you should be okay but dont expect a huge yeild reflux at 55 for 24 hours

 

[TheNut22]

yes thats alot of glacial acetic acid there should also be acetone in there too but with the extra acetic you should be okay but dont expect a huge yeild reflux at 55 for 24 hours

billythekidI got ~ 7 grams of sweet smelling little bit yellow P2P from 35 grams of MPB. My peracetic oxid time was around 24 h.
Now I've done the Leuckart reaction, at 32 h time. I have my n-formyl --... now. I am proceeding hydration with base (KOH pellets with pure water, 5 hours reflux), with that kind of reaction some paper claimed as good as 95% yield!?
I don't know, but this time, the look (got purple solution, but it's OK) and smell is different from my many attempts to proceed the Leuckart reaction, but I think I didn't have P2P then, but now I certainly did! Yes! Just never give up!
Because this was my 22:nd attempt..

 

[Fenster]

D

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.

G.PattonDCM 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]

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?

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

 

[Mo0odi]

Hydrogen peroxide (H2O2) 1300 g 50 %;

William DampierIs there an alternative to peroxide hydrogen ?

 

[Ortist]

Is there an alternative to peroxide hydrogen ?

Mo0odiOriginal twodogs procedure uses perboric acid made in-situ from acetic acid & sodium perborate. Perboric route is a bit messy and requires filtering

 

[TheNut22]

Original twodogs procedure uses perboric acid made in-situ from acetic acid & sodium perborate. Perboric route is a bit messy and requires filtering

OrtistI used one time performic acid, and it worked, but not as well as peracetic acid.

 

[TheNut22]

When I extracted my P2P with ethyl acetate, I put little bit of drying agent in, and put it in my fridge.
I looked the liquid, and when it was about 3 hours i the fridge, the bottom layer was full of clear oil.
Is that my P2P? Can I really extract with this way?!

 

[TheNut22]

When I extracted my P2P with ethyl acetate, I put little bit of drying agent in, and put it in my fridge.
I looked the liquid, and when it was about 3 hours i the fridge, the bottom layer was full of clear oil.
Is that my P2P? Can I really extract with this way?!

TheNut22I was just water in the bottom. But my P2P was in the ethyl acetate.