Syntéza alfa-PVP (stupnice 1-10 kg). Kompletní výukové video.
- Thread starter William Dampier
- Start date
Hey, i've made everything like in the Video but after I added Aceton and hcl to the freebase, it seperated into two layers. I've just put it to the freezer without seperating the two layers from each other. Is that okay?
- By lapgan1
I always have the same situation as you if I don't evaporate ethyl acetate, only when I evaporate ethyl acetate does it precipitate.
Greetings all! I can not understand the cause of black sediment at the bottom of the flask.
Here are my proportions for 500 grams of a-pvp
1. Bromvaleraphenone - 730 grams
2. ethyl acetate - 1600 ml.
3. Pyrollyddin - 360 ml
After I fully pour in the pyrollyddin, and stop the stirrer, a black precipitate starts to build up at the bottom of the flask.
I always keep the reaction temperature at 40-50 degrees!
What can this be?
Here are my proportions for 500 grams of a-pvp
1. Bromvaleraphenone - 730 grams
2. ethyl acetate - 1600 ml.
3. Pyrollyddin - 360 ml
After I fully pour in the pyrollyddin, and stop the stirrer, a black precipitate starts to build up at the bottom of the flask.
I always keep the reaction temperature at 40-50 degrees!
What can this be?
- By GeneralX
Next, I remove this black sludge through a separating funnel, and continue the process. And all is well, a-pvp comes out!
The big question is what is that sediment at the bottom?
The big question is what is that sediment at the bottom?
What causes a loss of 30-40% after drying? After filtration I get let's say 508 grams, after drying after 5-6 hours I get 300 grams. Is that normal? I always add EA before souring! I rinse a-pvp with cold acetone.
@William D. @G.Patton
Greetings
So after gaining enough theoretical knowledge, it was time to practice and I managed to get the reactions right the first time. The efficiency of this method is about 50%, which is still quite good for the first time. The syntheses were carried out on a much smaller scale because instead of 1000g, we started with 10g of 2BV with the correct proportions of Pyrrolidine and EtOH.
But something strange happened during the desalting of the apvp, or more precisely after about 60 minutes in the freezer most of the liquid turned into a frozen mush with the consistency of soft clay (visually). We decided to filter some of this slurry and, surprisingly, 1.5h after starting the synthesis, we had a ready-made portion of pure Alpha-PVP on the plate. HCl.
Suspiciously, we just got a bit lucky and the whole synthesis went perfectly and we were lucky with the purity of the reagents used during the synthesis. The product came out really strong and efficient, with doses of 50mg doing the job.
In addition, we were also able to obtain Apvp using HBr instead of HCl. The result was satisfactory despite a much lower yield.
Does anyone have any idea why the waiting time for the salt to precipitate differed significantly from that stated in the video?
Greetings
So after gaining enough theoretical knowledge, it was time to practice and I managed to get the reactions right the first time. The efficiency of this method is about 50%, which is still quite good for the first time. The syntheses were carried out on a much smaller scale because instead of 1000g, we started with 10g of 2BV with the correct proportions of Pyrrolidine and EtOH.
But something strange happened during the desalting of the apvp, or more precisely after about 60 minutes in the freezer most of the liquid turned into a frozen mush with the consistency of soft clay (visually). We decided to filter some of this slurry and, surprisingly, 1.5h after starting the synthesis, we had a ready-made portion of pure Alpha-PVP on the plate. HCl.
Suspiciously, we just got a bit lucky and the whole synthesis went perfectly and we were lucky with the purity of the reagents used during the synthesis. The product came out really strong and efficient, with doses of 50mg doing the job.
In addition, we were also able to obtain Apvp using HBr instead of HCl. The result was satisfactory despite a much lower yield.
Does anyone have any idea why the waiting time for the salt to precipitate differed significantly from that stated in the video?
Last edited:
Place 15 liters of methyl acetate in a cylindrical container containing 15 kg of 2'-bromovalerophenone and stir for 5 minutes.
2. Place a dropping funnel in the cylindrical container and add 15 liters of pyrrolidine.
3. Open the dropping funnel tap and add pyrrolidine dropwise while stirring vigorously.
4. Maintain the temperature below 65°C.
5. After the pyrrolidine addition is complete, stir the reaction mixture vigorously for 1 hour.
8. Add 1 liter of water to 1 liter of oil in the cylindrical container and stir for 10 minutes. Allow the water to separate and discard. Repeat this procedure three times. Rinse once with a solution of baking soda and water, making a solution of 80 g of baking soda per 1 liter of water.
9. Pour 15 liters of 96% ethyl alcohol into the washed oil and stir for 10 minutes.
10. Add hydrochloric acid (HCL) to the cylindrical container to adjust the pH to 5-5.5 (be careful not to overheat the cylindrical container).
12. Pour the reaction mixture into trays and place in the freezer for 72 hours.
13. Strain the contents of the trays through a sieve into a bucket.
14. Rinse the resulting crystals with ice-cold methyl acetate.
Yield: 70%
2. Place a dropping funnel in the cylindrical container and add 15 liters of pyrrolidine.
3. Open the dropping funnel tap and add pyrrolidine dropwise while stirring vigorously.
4. Maintain the temperature below 65°C.
5. After the pyrrolidine addition is complete, stir the reaction mixture vigorously for 1 hour.
8. Add 1 liter of water to 1 liter of oil in the cylindrical container and stir for 10 minutes. Allow the water to separate and discard. Repeat this procedure three times. Rinse once with a solution of baking soda and water, making a solution of 80 g of baking soda per 1 liter of water.
9. Pour 15 liters of 96% ethyl alcohol into the washed oil and stir for 10 minutes.
10. Add hydrochloric acid (HCL) to the cylindrical container to adjust the pH to 5-5.5 (be careful not to overheat the cylindrical container).
12. Pour the reaction mixture into trays and place in the freezer for 72 hours.
13. Strain the contents of the trays through a sieve into a bucket.
14. Rinse the resulting crystals with ice-cold methyl acetate.
Yield: 70%