Preparation of Bromvalerophenone for Alpha-PVP

[Madre]

We will present two methods for bromination of valerophenone for A-PVP.
This is the first.​

Bromination of valerophenone for a-pvp, method 1:

You will need:

1. Valerophenone (CAS 1009-14-9) 100g
2. Hydrobromic acid 48% (HBr) 29ml
3. Hydrogen peroxide 35% (H2O2) 19ml

This synthesis can be performed in a jar or even in a glass beaker. A long 1ml syringe can be used for mixing.

1) Place 100 grams of valerophenone in a glass and add 29 ml of bromic acid.

2) Use a syringe to measure 19 ml* (you can do this in parts) of hydrogen peroxide. Attach a tube to the syringe long enough to inject the hydrogen peroxide into the bottom of the jar.

3) The next step will require dexterity. With one hand, add the hydrogen peroxide drop by drop with the syringe, and with the other hand, stir the mixture. During the reaction, you will see the mixture begin to heat up. Each addition of hydrogen peroxide should give an indication. Look at the color of the mixture. The color can range from yellow to red. After the next batch has reacted and you have seen a reaction and discoloration, add the next batch of hydrogen peroxide. Continue until all the hydrogen peroxide has dripped out or the mixture is no longer discolored.
Stir the mixture very well, for 10-15 minutes, and move on to the next step.

4) Pour 200ml of distilled water into the jar and stir the mixture well, you can observe the separation into two fractions. The desired fraction (organic) will be at the bottom, the upper (aqueous) is sent to waste. The top fraction can be conveniently removed with a syringe and discarded. The lower fraction is washed with a solution of baking soda.

5) To do this, prepare a solution of 20g sodium bicarbonate (baking soda) dissolved in 250ml of water in a jar. Add the obtained bromvalerophenone to the solution and stir well for 10-15 minutes.

6) Then let the mixture stand. Again there will be a division into two factions. Repeat the separation as in step 4. The organic phase is bromvalerophenone at the bottom and a washing solution of baking soda at the top.

7) Bromvalerophenone is a yellow/light brown to red/dark colored liquid. Highly corrosive, fumes irritate mucous membranes and can damage skin. Store in plastic or glass containers with tight-fitting lids in a dark, cool place.
​

That's all. With Bromvalerophenone you can cook Alpha-PVP without any issues.
Next we will tell you about the second method for bromination of valerophenone​

 

[airsoft45]

in your guide for A-PVP in four steps you need *Alpha-bromvalerophenone, but the chemical being made in the guide on this page is Bromvalerophenone. how do i synthesize Alpha-bromvalerophenone and not just Bromvalerophenone?

thanks for help

 

[Ukspice]

Any reply to this question?

Does anyone know the answer

 

[61-50-7]

this is same

 

[Osmosis Vanderwaal]

Note; valerophenone=butyl-phenyl KETONE

A H2O2/HBr system – several directions but one choice: oxidation–bromination of secondary alcohols into mono- or dibromo ketones

In this work we found that a H2O2–HBr(aq) system allows synthesis of α-monobromo ketones and α,α′-dibromo ketones from aliphatic and secondary benzylic alcohols with yields up to 91%. It is possible to selectively direct the process toward the formation of mono- or dibromo ketones by varying the...

pubs.rsc.org

 

[Osmosis Vanderwaal]

I should also mention. Often people try to obfuscate what chemical they are using it selling. I see 2-bromovelarophenone/a-bromovelarophenone sold under the name
2-bromo-1-phenyl-1-pentanone

 

[komkom]

Yes that's it
CAS# 49851-31-2

 

[komkom]

Yes that's it
CAS# 49851-31-2

 

[komkom]

Yes that's it
CAS# 49851-31-2

 

[Osmosis Vanderwaal]

@komkom
Yes that's it,
CAS# 49851-31-2

 

[The Silent Chemist]

Hey all any help would be much appreciated, I had my first attempt at the apvp synthesis today.

During stage 1 halogenation, I followed the procedure excatctly as the video discribes adding the H202 slowly to the reaction vessel that contains the valerophenone and hydrobromic acid, ensuring the temperature did not exceed 60c.

I noticed that the red bromine colour persisted and did not go away after adding 2/3rds of the 43g of H202. I took this as my visual cue to not add any more peroxide.

(I assumed this was because I concentrated my peroxide from 6% to the 37% via boiling off the water under vacuum and I may have over concentrated it a little)

I let the reaction mixture stir for 10mins to ensure that the red colour would not go away. It did not.

shortly after adding 500ml of distilled water to the reaction the bottom bromovalerophenon layer turned from red to milky white.

my guess is I did not add enough peroxide and let the reaction stir long enough. I have discarded it and will try again.

any help would be appreciated