Benzaldehyde and MEK - TwoDogs Method
- Thread starter lalalander
- Start date
can anybody provide me receipt to it
- By lalalander
When 10 grams of Benzaldehyde + 10 grams of MEK and 7 grams of 30.5% aqueous HCl are mixed for 24 hours at room temperature, I obtain an organic layer.
The reaction should be carried out in an inert reactor, and the mouth of the reactor should be sealed with an inert stopper (such as LDPE, Teflon, glass, etc.).
I wash the organic layer with NaHCO3 solution until it is neutral and put it directly into the freezer. No heating. I filter it using a vacuum cleaner motor. This separates the remaining residual Benzaldehyde and MEK. White crystals remains behind.
When I pour -18 degree methanol on it, I obtain completely snow-white crystals. In my last test, I used 50 grams of Benzaldehyde + 50 grams of MEK and 35 grams of 30.5% aqueous HCl. I obtained 46 grams of snow-white crystals.
Methanol must be cooled in the freezer. Otherwise a lot of crystal will dissolve in the washing step.
I also think you can use ice water when washing, but I haven't tried it yet.
The reaction should be carried out in an inert reactor, and the mouth of the reactor should be sealed with an inert stopper (such as LDPE, Teflon, glass, etc.).
I wash the organic layer with NaHCO3 solution until it is neutral and put it directly into the freezer. No heating. I filter it using a vacuum cleaner motor. This separates the remaining residual Benzaldehyde and MEK. White crystals remains behind.
When I pour -18 degree methanol on it, I obtain completely snow-white crystals. In my last test, I used 50 grams of Benzaldehyde + 50 grams of MEK and 35 grams of 30.5% aqueous HCl. I obtained 46 grams of snow-white crystals.
Methanol must be cooled in the freezer. Otherwise a lot of crystal will dissolve in the washing step.
I also think you can use ice water when washing, but I haven't tried it yet.
↑View previous replies…
- By LabPsycho
If someone advice to use some buffer, I'll use it. It's not "buffered route" anymore... hehh.. I'm not very experienced in chemistry but I take advices from people, if it matches what I've learned from papers or I just don't know. But I say it is good to buffer the solution to get the peracid little bit less aggressive oxidant, or another words, little bit less active. To put little break, so the oxidation doesn't give side products, like you said you have some unknown shit in it (I don't know right words or the whole mechanism). In Rhodium Chemistry site has the procedure that I follow, but in there it is used to make MDMA, but that procedure can be used to P2P also.
Or any other ketone... It is said there that you should try to even use 25 g of sodium acetate to make the oxidation smoother reaction. I just use carbonate. I think that's why I get 85% to even straight 100% molar yield, when I make the reaction neutral, or close to neutral. Because now I had 75% yield because I had some "overflow" with my sodium carbonate, and therefore parts of the carbonate was all over my lab's tables safety glass. So, the mixture was bit acidic. And I noticed the product was red, because of that. When I started to hydrolyze it with a base, it turned yellow in the beginning of hydrolyzation. That observation of mine confirmed that I was right.
Or any other ketone... It is said there that you should try to even use 25 g of sodium acetate to make the oxidation smoother reaction. I just use carbonate. I think that's why I get 85% to even straight 100% molar yield, when I make the reaction neutral, or close to neutral. Because now I had 75% yield because I had some "overflow" with my sodium carbonate, and therefore parts of the carbonate was all over my lab's tables safety glass. So, the mixture was bit acidic. And I noticed the product was red, because of that. When I started to hydrolyze it with a base, it turned yellow in the beginning of hydrolyzation. That observation of mine confirmed that I was right.
- By lalalander
"I think it is ready-to-use peracid..."
Oxone is the triple potassium salt of Caro's acid prepared with 1:1 H2SO4 and H2O2, brought to pH 2 with 45% potassium hydroxide solution and precipitated after cooling. So, you are correct. It is a potassium salt of a peracid.
Oxone is the triple potassium salt of Caro's acid prepared with 1:1 H2SO4 and H2O2, brought to pH 2 with 45% potassium hydroxide solution and precipitated after cooling. So, you are correct. It is a potassium salt of a peracid.
- By LabPsycho
Thanks for the info, but I'm not really into that. I just want to have new.. new kind of experiences with success. Yea, that's it why now when I've learned so much in 5 years, but VERY much in a 1 year, I want to put my knowledge into use, and when I'm good for example to make pretty pure (density 1 g / 1 ml) P2P with investing some months just 5-6 local "dollars",
I'm just like:
"This is fucking FUN! I like this!". I love this... But yeah. You knew all that, and still you ask... ummm.. I don't get you. Let me know if I can help you with a problem (with my limited knowledge), because you already seem to know enough. Someone might think you're a police officer!
Joke.. And have a nice day!
I'm just like:
"This is fucking FUN! I like this!". I love this... But yeah. You knew all that, and still you ask... ummm.. I don't get you. Let me know if I can help you with a problem (with my limited knowledge), because you already seem to know enough. Someone might think you're a police officer!
Joke.. And have a nice day!
- By lalalander
I am very interested in chemistry, but I am not very knowledgeable except for BV oxidation (in terms of knowing the procedures xd). In the last 2 years, there is almost no book I haven't read about BV oxidation. When you read the procedures, it seems unreal. It's like if you repeat it, it won't happen. But it is really gratifying to witness the result.
- By lalalander
Maybe you won't believe it, but when I was practicing the perborate method, I was positive for coronavirus and I couldn't smell anything, so I don't know whether the smell I smell is due to the ester or not.
The liquid I obtained today, which I suspect is an ester, smells like this; Medicinal/styrene top note, burning, extremely intense synthetic sweetness. It's a bit like benzaldehyde. It doesn't smell like MPB and it doesn't freeze in the freezer but its viscosity increases.
The liquid I obtained today, which I suspect is an ester, smells like this; Medicinal/styrene top note, burning, extremely intense synthetic sweetness. It's a bit like benzaldehyde. It doesn't smell like MPB and it doesn't freeze in the freezer but its viscosity increases.
- By lalalander
I think so too. When I treat it with base, the color becomes very dark orange. After 2 hours, I make pH 7 with acetic acid. The color turns yellow again. But I don't observe any change in smell. Now I'm going to steam distill it.
- By lalalander
I had done it like this: I added MPB directly into peracetic acid without using a solvent and left it on its own for two days without stirring, assuming it had failed. Later, when I added the MPB + peracetic acid mixture, which had been left to stand for 2 days, into an Oxone, methanol, and water mixture, my entire house was suddenly filled with this smell. Most likely, what I had added was not MPB + peracetic acid, but an ester. Oxone provided an acidic environment, which led to hydrolysis with the methanol + water mixture, directly yielding P2P. This is probably why I did not observe a change in smell during basic hydrolysis, because what I had already obtained was likely P2P.
- By lalalander
I sent it to a private lab for NMR testing. What I got was not the ester, but 1-phenyl-1,2-propanedione, aka racemic PAC. Apparently the peracetic acid oxidation worked, but when I thought it didn't work and re-oxidized it, the enol ester epoxidized. It's incredible to me that I've come up with an estimate so close to the odor profile described in the literature.
If 2.5 mol of peracetic acid is used for every 1 mol of 3-methyl-4-phenyl-3-buten-2-one, oxidation to the enol ester and subsequent epoxidation of the double bond in the enol ester takes place. This is then hydrolyzed resulting in 1-phenyl-1,2-propanedione. It can be used to synthesize racemic ephedrine.
I am now working with one-pot 40% H2SO4 and Oxone route. 24 hours, at room temperature. Extraction, washing, evaporation of DCM and steam distillation gives apple smelling P2P in nice yields.
If 2.5 mol of peracetic acid is used for every 1 mol of 3-methyl-4-phenyl-3-buten-2-one, oxidation to the enol ester and subsequent epoxidation of the double bond in the enol ester takes place. This is then hydrolyzed resulting in 1-phenyl-1,2-propanedione. It can be used to synthesize racemic ephedrine.
I am now working with one-pot 40% H2SO4 and Oxone route. 24 hours, at room temperature. Extraction, washing, evaporation of DCM and steam distillation gives apple smelling P2P in nice yields.
- By LabPsycho
Well, I think 1-phenyl-1,2-propanedione that you've made is VERY useful chemical. Can you elaborate what does it cost to send it to lab testing? Of course there are thousands of options and prices, but what I don't get, is that you thought you had failed, and then oxidized the compound again? Why? You don't believe the process and make your own extra steps to make it so it is defenietly some unknown molecule?! Then pay some company to test it? Bullshit!
- By lalalander
It's okay. We're all human beings.
---
It would make a lot of sense if I wrote all my tests on a chronological timeline; you'd see that they all have really logical explanations.
When I performed oxidation with pre-prepared peracetic acid, I was left with a crystallized liquid. Since I used a buffering agent, I thought these were sodium acetate crystals.
However, when I didn’t use a buffering agent, I noticed that I obtained crystals with a strong acetic acid smell, and no matter how much I washed them, the smell wouldn’t go away.
These crystals also had a lower melting point than the starting ketone. I never encountered this in an in-situ reaction.
That’s why I thought the crystals were the unreacted aldol product, and since everyone said I should have smelled a "sweet aroma," I assumed the reaction was a failure.
In Böeseken's article, he stated that this ester could form two isomers and give a semi-liquid, semi-solid ester.
The acetic acid smell was due to partial hydrolysis because when the acetoxy ester undergoes hydrolysis, it forms P2P and acetic acid. It took me a while to put all the pieces together.
Although I'm still not entirely sure whether what I obtained is P2P, it should be. I performed a reductive amination, but I’m not keen on using the product without confirming its identity.
It freezes between -15 and -22 degrees, and when I take it out of the freezer, it turns liquid again within a short time.
As you know, aldol products maintain their crystalline form once frozen. This is definitely not the aldol product. But we will see.
---
It would make a lot of sense if I wrote all my tests on a chronological timeline; you'd see that they all have really logical explanations.
When I performed oxidation with pre-prepared peracetic acid, I was left with a crystallized liquid. Since I used a buffering agent, I thought these were sodium acetate crystals.
However, when I didn’t use a buffering agent, I noticed that I obtained crystals with a strong acetic acid smell, and no matter how much I washed them, the smell wouldn’t go away.
These crystals also had a lower melting point than the starting ketone. I never encountered this in an in-situ reaction.
That’s why I thought the crystals were the unreacted aldol product, and since everyone said I should have smelled a "sweet aroma," I assumed the reaction was a failure.
In Böeseken's article, he stated that this ester could form two isomers and give a semi-liquid, semi-solid ester.
The acetic acid smell was due to partial hydrolysis because when the acetoxy ester undergoes hydrolysis, it forms P2P and acetic acid. It took me a while to put all the pieces together.
Although I'm still not entirely sure whether what I obtained is P2P, it should be. I performed a reductive amination, but I’m not keen on using the product without confirming its identity.
It freezes between -15 and -22 degrees, and when I take it out of the freezer, it turns liquid again within a short time.
As you know, aldol products maintain their crystalline form once frozen. This is definitely not the aldol product. But we will see.