4-MMC (mephedrone) synthesis. Bromination in dichlormethane.

[Serega]

Looks nice. Only ideal conditions for bromination need to be changed. The easiest way to brominate with virtually no odor is to brominate in DCM under a layer of water. Water absorbs hydrogen bromide, thus the smell and gases are practically absent in the external environment.
Thus, 50-100 liters of ketone can be brominated at a time.

Hank SchraderUnder water +1

 

[Chemix-Express]

I am very interested in your comment. Someone has already mentioned this here on the forum.

I plan to set the temperature rigidly at 34 degrees (half of the given range of 32-36 degrees) and the reaction time at 4h.

The person who gave this information also gave proportions for this reaction.

Namely:
- 100g bk4
- 250ml DCM
- 150ml m40

1. will these proportions of reagents be correct?
2. i am to add 1/2 m40 at the beginning and 1/2 m40 after one hour of reaction. What is the purpose of this? I understand to tame the temperature, but what difference does it make if we do it in 1 go or spread it over two approaches?

I have already had one approach to this attempt. I added everything in the proportions as above. I heated the mixture to 20 degrees and started adding the m40. Unfortunately the temperature did not start to rise on its own. After starting the heating from outside, the temperature suddenly jumped to 40 degrees. The liquid was boiling and turning off the heating did not help.

What I think. Heat the reaction mass to 25-30 degrees before adding the m40 and only start gradually adding the m40 so as not to exceed the mentioned 36 degrees? Is this OK? Or do I heat the whole thing up to the reaction temperature of 34 degrees and only then add the m40?

I have one more question. How do I clean the free base?

Washing the free base twice with an equal volume of 10% sodium trisulphate solution to remove any remaining bromoketone and washing it 2 times with clean water is sufficient? Is it necessary to use something else?


Why is it that when I neutralise with hydrochloric acid in acetone to pH 6, when adding the HCL:acetone mixture to the free base it starts to turn colourful. It's terribly difficult to wash the powder to snow white afterwards.

The colours that have occurred to me are blue, green, dark red and pink.

 

[subzero013]

I am very interested in your comment. Someone has already mentioned this here on the forum.

I plan to set the temperature rigidly at 34 degrees (half of the given range of 32-36 degrees) and the reaction time at 4h.

The person who gave this information also gave proportions for this reaction.

Namely:
- 100g bk4
- 250ml DCM
- 150ml m40

1. will these proportions of reagents be correct?
2. i am to add 1/2 m40 at the beginning and 1/2 m40 after one hour of reaction. What is the purpose of this? I understand to tame the temperature, but what difference does it make if we do it in 1 go or spread it over two approaches?

I have already had one approach to this attempt. I added everything in the proportions as above. I heated the mixture to 20 degrees and started adding the m40. Unfortunately the temperature did not start to rise on its own. After starting the heating from outside, the temperature suddenly jumped to 40 degrees. The liquid was boiling and turning off the heating did not help.

What I think. Heat the reaction mass to 25-30 degrees before adding the m40 and only start gradually adding the m40 so as not to exceed the mentioned 36 degrees? Is this OK? Or do I heat the whole thing up to the reaction temperature of 34 degrees and only then add the m40?

I have one more question. How do I clean the free base?

Washing the free base twice with an equal volume of 10% sodium trisulphate solution to remove any remaining bromoketone and washing it 2 times with clean water is sufficient? Is it necessary to use something else?


Why is it that when I neutralise with hydrochloric acid in acetone to pH 6, when adding the HCL:acetone mixture to the free base it starts to turn colourful. It's terribly difficult to wash the powder to snow white afterwards.

The colours that have occurred to me are blue, green, dark red and pink.

Chemix-ExpressYou will need to cool, and not heat if you want to do at a temperature of 34 degrees. After adding methylin in 10 - 15 minutes, the mixture will begin to self -heal, heated bromketon before adding methyline. It is not particularly clear why exactly 34 degrees, dichlormethane boil with dissolved bromketon will be at high temperatures. When acidic, acetone often gives the color to Mephedron, someone recommends that it use ethylacetate instead and acidify with salt -acid isopropanol, someone to sour with water and then remove it.

 

[Chemix-Express]

You will need to cool, and not heat if you want to do at a temperature of 34 degrees. After adding methylin in 10 - 15 minutes, the mixture will begin to self -heal, heated bromketon before adding methyline. It is not particularly clear why exactly 34 degrees, dichlormethane boil with dissolved bromketon will be at high temperatures. When acidic, acetone often gives the color to Mephedron, someone recommends that it use ethylacetate instead and acidify with salt -acid isopropanol, someone to sour with water and then remove it.

subzero013Hi. After reconstitution of BK4 in DCM (25-26 degrees C), the flask was placed on the agitator and the maximum stirring was turned on. Heating is disabled. The entire m40 was added at once, after 5-10 min the temperature began to rise to 35-37 degrees in 30-35 minutes, after which it began to fall down on its own. You mentioned that the whole reaction should last about 3.5-4 hours and will end when the temperature automatically begins to drop. For me, it warmed up to only 35-37 degrees in 30-35 and began to fall down. What am I doing wrong?

 

[StarWars]

how to calculate the amount of dcm in this synthesis??

 

[G.Patton]

how to calculate the amount of dcm in this synthesis??

StarWarsproportionately

 

[WhalterWhite]

I tried this method x ready 2b4chloro. I got cold soft rocks. After cleaning with acetone, the yield was low +- 20%.

 

[WhalterWhite]

This after 12 h freezer

 

[Zetetic]

We'll consider mephedrone (4MMC) synthesis in this article. Dichloromethane (DCM) is used as a solvent. It has a low boiling point (~40 °C) and synthesis procedures take a little time.​

Work conditions:

• Air temperature 20-24 ºC;
• Relative humidity <60%;
• Well-ventilated room (with air intake/exhaust hood);
• Access to water and electricity;

Main stages:

1. Bromination;​

2. Methylamination;​

3. Separation/cleaning of the free base;​

4. Acidification;​

Bromination

View attachment 904​

1. 4'-Methylpropiophenone (cas 5337-93-9) 1000g and DCM 3000 ml is placed into a 10 l flask, stirred until a homogeneous solution is obtained.
2. A portion of bromine (Br2) 1000 g, 330 ml is poured into a drip funnel.​

​

It is important to know: Work with bromine takes special safety measures because the substance is very corrosive and toxic. Every surface, which has contact with bromine, will be completely spoiled. It is better to use long graduated pipette or graduated cylinder in order to measure volume of this substance. Bromination have to be carried out outside or in a well-ventilated room by reason that bromine is very volatile. The procedure isn't tricky but takes an attention. All glassware, which will be used for manipulations with bromine, must be cooled and absolutely dried.

3. Hydrochloric acid (HCl 36% aq) 50 mL is added into the reaction mixture. It is the catalyst of bromination reaction. A weak stirring is turned on and bromine addition is started.
4. The first portion of bromine ~50 ml is added. The solution is turned brown and eventually is discolored. It means that the bromination reaction is taken place. You have to wait this moment, and not pour out all bromine in a one portion to avoid a violent exothermic reaction with a subsequent boiling off of the solution.
5. Bromine is added from the drip funnel to the solution dropwise, when the first Br2 portion is discolored, in order to a smooth reaction course. If the solution begins to boil, the addition of bromine have to be stopped until the solution is cooled to 30-35 ºC.
​

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It is important to know: Hydrogen bromide is released during bromination. It is the caustic white gas (acid). It takes respiratory organs and eyes protection (full face mask) and well ventilated exhaust fumes hood.​

View attachment 714 ​

6. It is necessary to make sure that the reaction has been completed after all the bromine has been poured in: reaction temperature is stopped to rising, the solution is stopped to discoloring. Then, the reaction mixture is stirred for 30-60 min.

7. Obtained solution is washed from remaining bromine, it positively influence on the final product quality. The reaction mixture is washed with an equal volume of sodium thiosulfate (Na2S2O3) 10% solution or sodium bicarbonate (NaHCO3) 10% solution. The solutions is stirred well for 10 min, layers are clearly separated. The lower organic layer is taken for further manipulations. The top layer is disposed.

8. Next, the reaction mixture is washed with an equal volume of water to neutral pH. The washing procedure of the organic layer can be repeated several times, if it is necessary. The reaction 2-Bromo-4'-methylpropiophenone (cas 1451-82-7) yield is ~1400g, which is already dissolved in DCM.​

Methylamination

View attachment 905​

9. Methylamine 40% aqueous solution is added to the solution from previous reaction. This reaction is also exothermic, so that methyl amine is added at slow rate in order to avoid the solution boiling. This influences on the reaction yield. Methylamine is taken in excess by reason that it is partially evaporated during the reaction. The average proportion is 2 ml per 1g of 2-Bromo-4'-methylpropiophenone. Methylamine 40% aqueous solution 2800 ml is added to 2-Bromo-4'-methylpropiophenone 1400 g. Methylamine is added via drip funnel in a thin flow or It is divided to 2-3 portions and poured in equal portions with a moderate stirring without splashing.

10. The reaction mixture is stirred for 2 h at 40 ºC.​

View attachment 716 View attachment 715
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Free base separation and purification
11. After the mixture from the previous part is processed, the free base is washed and separated. The lower organic layer is separated from the upper aqueous layer. The organic layer is washed as described in step 7 (same procedures), the upper layer is scrapped. The organic layer washing is repeated several times until methylamine smell is disappeared.​

View attachment 771 ​

12. The mephedrone (4-MMC) free base DCM solution yield is ~3000 ml. If the organic layer is too small after methylamination, pour DCM 1-2 L. This will help to extract 4-MMC free base better. Then, layers are separated and an aqueous layer is disposed.

13. It is very important to separate the organic layer from the water. To be sure, you can put the DCM solution in the freezer, the remaining water will freeze and easy to separate. Also, you can dry your solution by anhydrous magnesium sulphate (MgSO4). If the water is left, problems with precipitation in the next step can happen during acidification.​

Acidification

14. The resulting mephedrone free base in the DСM is treated with hydrochloric acid. The best way salt production is HCl gasification. A 35-38% HCl hydrochloric acid water solution in acetone or isopropanol is also used in the ratio of 1 ml of hydrochloric acid per 10 ml of solvent (1:10).

The acid is added in small portions with a constant stirring. If the reaction mass become to thick, it is diluted with acetone. The mixture should be liquid enough in order to acidify 4-MMC free base evenly. White gas (HCl) is actively released during this procedure. Respiratory organs and eyes protection have to be used. In order to minimize the release of gas, it is recommended to cool the solution. During the acidification process, it is important to control the pH. At 5.5-6 pH, the acidification is stopped. The mixture is put into a freezer for several hours. After that, the product is filtered and dried. pH is controlled with pH indicator paper.​

View attachment 6846​

Purification and crystallization instructions:

Mephedrone (4-MMC) powder purification

Introduction Mephedrone (4-MMC) synthesis reaction is carried out with production of some amount by-products. Also, some amount of unredacted precursor is left in the reaction mixture after reaction. It takes to purify a 4-MMC product with insufficient purity to reduce health risks. Manual As...

bbgate.com

https://bbgate.com//index.php?threads/crystallization-of-mefedrone-4mmc.72/

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Marvin Popcorn SuttonI greet you gentlemen! what can replace dichloromethane? available are benzene, acetone, isopropyl alcohol, ethyl acetate, petroleum ether. hope for a quick reply. five hours left and the lab will be closed.

 

[StarWars]

This is what im het thanks guys for help

 

[Marvin "Popcorn" Sutton]

I greet you gentlemen! what can replace dichloromethane? available are benzene, acetone, isopropyl alcohol, ethyl acetate, petroleum ether. hope for a quick reply. five hours left and the lab will be closed.

ZeteticBenzene will work fine, but the methodology will change a bit. PM me and I'll tell you everything in detail.

 

[Chemix-Express]

Benzene will work fine, but the methodology will change a bit. PM me and I'll tell you everything in detail.

Marvin &quot;Popcorn&quot; SuttonCan I also ask for some tips on the reaction to benzene? Currently, on benzene, the yield on crystal is around 53-55%. Maybe something will be useful. Regards and alletings

 

[StarWars]

Dont use

pozdrawiam Panowie! czym można zastąpić dichlorometan? dostępne są benzen, aceton, alkohol izopropylowy, octan etylu, eter naftowy. nadzieję na szybką odpowiedź. jeszcze pięć godzin i laboratorium będzie zamknięte.

ZeteticBezen is toxik use toulen or dcm

 

[G.Patton]

Dont use

Bezen is toxik use toulen or dcm

StarWarsIn fact, they are also toxic. With appropriate protection (well-ventilated area and face mask), any harm can be multiplied by 0.

 

[breathing.fire]

Anybody try do this with methylamine 33% in methanol?

 

[Marvin "Popcorn" Sutton]

Anybody try do this with methylamine 33% in methanol?

breathing.fireYes it works.

 

[euphoria84]

I found this on a Russian forum, according to them, 100% Bromoketone reacts in 7 hours at 30 degrees Celsius

 

[w2x3f5]

I found this on a Russian forum, according to them, 100% Bromoketone reacts in 7 hours at 30 degrees Celsius

euphoria84Author Linx (banned) the information is not reliable. The reaction in dichloromethane takes an average of 2 hours at 30 degrees.

 

[StarWars]

Police chemist say 24h in 20°c with toulen is much synthesis best is fast pure and much.

 

[euphoria84]

Police chemist say 24h in 20°c with toulen is much synthesis best is fast pure and much.

StarWarswith toluene to form pyrazine

 

[breathing.fire]

If I don't have acetone or IPA I can replacement them with other alcohol like methanol or ethanol?

 

[hexen]

If I don't have acetone or IPA I can replacement them with other alcohol like methanol or ethanol?

breathing.fireNo only ethyl acetate

 

[Marvin "Popcorn" Sutton]

If I don't have acetone or IPA I can replacement them with other alcohol like methanol or ethanol?

breathing.fireThe alcohols have to be of good quality to fit. IPA is the most readily available. Methyl and ethyl should also work, but they are harder to find the right quality.