Phenylacetone (P2P) synthesis from benzaldehyde with butanone

[Ortist]

saponification in aqueous NaOH at 50 degrees ?! Thats really bad idea

 

[gmo]

What temperature is required?

 

[mckennai]

Are you already in try or just asking? I'm almost trying that recipe just Williams guiding and directing me. I think I've done obtaining first intermediate I'had 3butane2one now I'm on acetoxy synthesizing step 2. If u already trying to synthesize Ill be happy to talk and stayin contact with u

 

[gmo]

I tried unsuccessfully once, now I want to start again with the mentioned combined method and the opinions of friends and some simple initiatives. I will be happy to cooperate with you

 

[lalalander]

Everyone says this method has flaws. Has anyone ever really gotten significant yields with this method?

 

[Ortist]

I used this method many times. Modified a bit. The best results I got was 30ml of P2P from 100ml of benzaldehyde. Also I know a few people who researched this reaction alot; their best results were around 35ml of P2P.

Working method:

1. Methyl-phenyl-butenone prepared as follows: 500ml of benzaldehyde is mixed with 1000ml of MEK. Mixture is cooled in a bucked filled with ice to around +5 degrees.
2. To this is added aqueous HCL, 35-37%, (you have to add 100g of pure HCL which corresponds to about 286ml of 37%HCL)
3. Mix and keep it in a bucket with ice overnight, let the ice melt.
4. Wait 24 hours more
5. Put it in a separatory funnel, discard lower layer.
6. Wash the dark brown-red mixture with 500ml of water, discard water.
7. Distill everything that boils below 150 degrees at atmosferic pressure and discard
8. Distill the rest in vacuum to get a yellow oil

This oil will darken on standing within a week.


Bayer-Villiger:
1. 100ml of above prepared oil add to mixture of 300ml of glacial acetic acid and 100ml of 50% hydrogen peroxide.
2. Heat & stir it at 55 degrees.
3. When reaction starts temperature will go up above 55..60 (about 1..2 hours) : this is the indication to turn OFF heating. If temperaturfe climbs to 70 then cool your flask under running water a bit.
4. Stir until temperature falls back to 50..55 degrees, then turn heating ON again
5. Stir & heat for 6 hours
7. Pour mixture to 1L of water, extract 3 times with 100+100+100ml of DCM
8. Distill DCM off


Saponification:
1. Put Bayer-Villiger product from the step above in a flask with stirring. Slowly add
NaOH solution (30g NaOH, 250ml water, 250ml ethanol). Slowly means dropwise, about 3..5 drops a second. Mixture becomes reddish-orange

2. At the end of addition pH should be above 12
3. To the mixture add acetic acid (any percentage) until neutral pH. Mixture will turn yellow
4. Pour this to 1L of water and extract 3 times with 100+100+100ml of DCM
5. Distill DCM & traces of ethanol off at atmospheric pressure
6. Distill your P2P under vacuum.
7. There will be alot of tar left in a flask

 

[gmo]

Can I use chloroform in Saponification step 4 extracted?

 

[Cbison]

Is the alkaline wash of MPB necessary? I noticed you didn’t do that but distilled after the water wash

 

[Ortist]

You can also distill P2P with water, but it is very slow. However you MUST distill methyl-phenyl-nutenone under vacuum because there is significant amount of crap and MPB will not distill with water

 

[gmo]

Thank you very much,how L-meth can be turned into racemate?and why in Mexico can use al/hg method in large scale?

 

[Xiao hua]

even hcl has bubbled 1.5h.Why not add Hcl liquid? Why. Can someone explain me. Thanks

 

[Ortist]

You can use aqueous HCl. Just use 1 liter of benzaldehyde to 2 liters of MEK and calculated amount of 35..37% hydrochloric acid. You need 20g of PURE HCl per each 100g of benzaldehyde. So 1L of benzaldehyde will require 200g of PURE HCl. Now calculate how much aqueous acid do you need.

With gaseous HCl you'll get a bit better yeld and a bit less sideproducts. But in my opinion it doesn't worth it especially on big scale. Also with aqueous HCL you have to use more MEK otherwise your HCl will separate on the bottom too early.

"Gas for 1.5 hour" is WRONG. You have to gas until you get 20g of gas into each 100g of benzaldehyde. How long it can take nobody knows.

 

[Ortist]

See post #121 above on this page

 

[Xiao hua]

How bro. in this page no have 121

 

[Xiao hua]

Bro what can instead of chloroform in step one?

 

[Ortist]

Phenylacetone (P2P) synthesis from benzaldehyde with butanone

Everyone says this method has flaws. Has anyone ever really gotten significant yields with this method? I used this method many times. Modified a bit. The best results I got was 30ml of P2P from 100ml of benzaldehyde. Also I know a few people who researched this reaction alot; their best...

bbgate.com

 

[Xiao hua]

Bro how to separate isomers of amphetamine and meths

 

[mckennai]

Can we correct something??? You saying magnesium sulphate anhydrous and giving Na2SO4 and one of the steps u saying mgso4 for it again.. Can you be clear for exact item and with exact values?? For usage and for buying.. We need to know amount that we need to get and use.. U didnt give any value for how much amount of that mgso4 or na2so4 we need... Thanks

 

[waltjr5858]

For the magnesium sulfate since it's just used for drying you can put in any amount you want really. There's not really a specified amount to put in but depending on the scale of what you're doing.... like if I was going to try something that was let's say 200 mils of oil or whatever you got I would probably toss 15 or a 20 G or so of magnesium sulfate in there and maybe steer it around for a little bit and an hour or so later come back and vacuum filter it right out of there. If the procedure you're doing has to be strictly anhydrous you could do the same thing over again maybe even three times if you want to make sure you get any and all water out of there. For this once is plenty

 

[mckennai]

Can we correct something??? You saying magnesium sulphate anhydrous and didnt give the exact values how much we need to get.. And second one u saying "na2so4" in brickets but one of the writings in your steps somewhere u saying "mgso4". Actually magnesium sulphate mgso4 but na2so4 sodium sulphate.. Please can you give exact item with net-clear values for usage

 

[gmo]

Thank you very much,how L-meth can be turned into racemate?

 

[WillD]

Maybe with some temperature exposure this is possible. But we don't know for sure.

 

[mckennai]

Im doing this one with two different way. 1. Williams method qnd lalalander's experienced topic. . 2. Sci hub.. im wondering about thread.. 1 waiting times 2, different reagents.. 3, totally differenr tactis..

Can somebody give a right and fastest way for p2p obtaining from benzaldehyde and mek?? Which way should i follow? Ive hcl and h2so4 for making hcl gas bubling but didnt used glasswares for dripping hcl over sulphuric acid with atmohsperic pressure glass setup, i just bought dosage pump and setted up for dripping selected amount of ml in hour over sulphuric acid.. is it ok anyway??. Or please write a route for me i couldnt do well that glassware setups for hcl gassing nd vacumming. Ill fix it for vacumming but i dont have any idea for doing right things for hcl gassing

 

[WillD]

Bunsen flask with silicone hose and syringe with hcl

 

[OrgUnikum]

Make this PE, polyethylene tubing (there should be no high temperature so no problem). Or PTFE tubing if you have too much money. Silicone tubing will disintegrate on contact with MEK, Benzaldehyde or Acetone. Instantly.

Source: Any chemical resistance chart and personal experience

 

[mckennai]

I really need your answer in pm williams it's very important for me today I hope u see and answer early as possible as you can :"(

 

[bigbadbear]

 

[bigbadbear]

For the second step, can I use a 15-liter flask ? and carry out the extraction process in a 50-liter plastic barrel?