Why do I always fail acidification?

[abis777]

So I have a problem with my 4mmc synthesis. everything seems to go well until the acidification process. So I have the freebase freezing cold, the same as acetone and acid hcl 32%. I put acetone 1ml on 1 in freebase (start ph is 7-8) then I start adding acid 1 drop a sec. Halfway the process (after 30ml acid 100g bk batch) I decide to measure and it's 1 or 2 and after I continue the ph becomes 0 (only last time I decided to continue after reaching ph 1 2 to see wtf it s going on). Happened every time. What do you think is the problem? The acid I have seems a bit shady, is sold as cleaning product. Do you think the acid is the problem?

 

[dnBQByvHb8Zkawbjpx]

There is something in your free base layer that should not be there. I've had this problem several times, per my understanding it was unreacted bk4 in my case. Focus on your initial reaction where stirring and temperature control are key. What solvent did you use, the amount, stirring method and how did you heat the RM? What amount of MMA, is it good or possibly stale with decreased potency?

The following photo and video are from my last cook where I used ethyl acetate, strong magnetic stirring and I heated the RM to 50-55 °C peak with the total reaction time of 30 minutes. The acidification was the cleanest job that I ever did.

 

[abis777]

for 100g bk i used 150 g methylamine hcl in ea no heat exothermic reaction. (temp about 45c) reaction time 30 min after adding all methylamine

 

[dnBQByvHb8Zkawbjpx]

I don't have experience with using MA.HCl but I've done some studying in preparation to switch to this method in the future. Usually it's used in combination with some base that helps with hydrolysis that frees MA gas into the solution. I've seen mostly NaOH used for this purpose. What did you use to release MA gas from the hydrochloride salt?

 

[abis777]

I used 100g NaOH dissoolved in 200ml

 

[abis777]

my magnetic stirrer is doing a hard job stirring all that methylamine

 

[abis777]

I think I have the same magnetic stirrer but with magnetic bar

 

[Aliexpress]

I did not measure the yield of this batch.

 

[dnBQByvHb8Zkawbjpx]

I did not measure the yield of this batch.

 

[dnBQByvHb8Zkawbjpx]

As for the acid, show us the exact HCl product that you are using. Find it being sold online or go to the manufacturer's website and download the safety sheet. In it you'll find detailed composition and whether it contains any coloring, adulterants, inhibitors or anything else. It should contain only HCl and water.

Oh and as I may have told you previously, I am not convinced about the pH levels that you are reporting. It cannot jump to 1-2 without you adding a large amount of acid at once, which you say you don't do. How exactly do you measure pH - with an electronic device or test strips? Give as much detail as possible. The amount of HCl is not enough to bring this amount of mixture down to pH 1-2 so there must be something wrong with the measurement.

Finally, per my experience 4MMC precipitates at around pH 5.5, so as soon as the pH of your mixture passes through this value and continues to go down you'll see any 4MMC in the mixture precipitate. Do you see any precipitate, half way or after using all acid you planned to use? How about any changes of color of the mix?

 

[abis777]

ph strips. I dip the strip then i take it out after 2 sec and read it

 

[dnBQByvHb8Zkawbjpx]

I see. Since you don't see any precipitate, that means there is no 4mmc free base, there is no HCl used up to form the salt of 4mmc and instead all HCl stays in the solution which brings the pH down rapidly. This is starting to make sense as if your amination reaction does not take place at all because you failed to convert MA.HCl back to MA free base form using some base in the RM.

 

[abis777]

really good explanation so far, thanks. What do you think is the reason for the failed conversion of ma hcl

 

[abis777]

First thing in amination reaction, I dissolve 100g bk in 500 ml EA than I add H2O + NaOH solution (1gNaOH 2mlH2O ratio) after I add instantly 1/3 of the ma hcl then adding the rest careffully so the temp does not get to hot, after I m done with that I let it stir for 30 min.

 

[dnBQByvHb8Zkawbjpx]

You should have given all this info right at the start to save everyone going back and forth getting all information.

Your method seems to be identical to that of a local scholar @Dr. MMX described here: Mephedrone (4-MMC) Synthesis [2B4M, Etyhyl Acetate, Methylamine HCl]. You use the same proportion of BK4, EA, MMA.HCl, NaOH and H2O, in the same order. Have you tried to hydrolyze MMA.HCl in NaOH solution to see if it smells as it should? Do you observe a color change during the reaction? And after the reaction, what color is the organic layer once layers separate?

 

[abis777]

yes, that s the method i use these are some pictures. this is the color of the meph before any wash (first pic). The second pic is from another batch also before any wash, after the washes the color gets closer to the first pic. from first pic batch I get almost clean white mix at acidification but with a weird ph like usual i think it was 2. From batch from pic 2 I get a more brown mix at acidification with same weird ph.

 

[abis777]

you can't really see how the color change wit the methylamine in the mix

 

[abis777]

I didn't try to hydrolize ma hcl

 

[dnBQByvHb8Zkawbjpx]

I can't judge this color as I have no experience using MMA.HCl. I've made 4mmc using BK4 in EA with MMA 40 %, and you can see the stirred RM in the photo above (the one with the bottle). After layer separation the organic layer was yellow-green, not reddish. @Dr. MMX may be kind enough to assess the color and advice further.

Try to dissolve a small amount of MMA.HCl in water and then mix it with NaOH+H2O solution. This should generate methylamine gas which you'll recognize by its characteristic smell. Also, what is the temperature of your RM during the reaction? MMA (or any gas, for that matter, AFAIK) solubility in water decreases as the temperature goes up. If your RM is too hot then it may not be able to keep MMA gas dissolved and it gets released instead. Dr. MMX mentions cooling of the RM in his post, do you control the temperature? How, and at what temp?

 

[abis777]

This is the HCL acid I used and this it s composition as it says in safety sheet:
SECTION 3. Composition/information on ingredients
3.1. Substances
Contains:
Identification Conc. % Classification 1272/2008 (CLP)
HYDROCHLORIC ACID 32%
CAS 7647-01-0 32 Met. Corr. 1 H290,
Skin Corr. 1B H314,
Eye Dam. 1 H318,
STOT SE 3 H335,
Classification note according to Annex VI of the CLP Regulation: B
EC 231-595-7 Skin Corr. 1B H314: ≥ 25%, Skin Irrit. 2 H315: ≥ 10%, Eye Dam. 1 H318: ≥
25%, Eye Irrit. 2 H319: ≥ 10%, STOT SE 3 H335: ≥ 10%
INDEX 017-002-01-X
Reg. REACH 01-2119484862-27
The full text of the hazard statements (H) is reported in section 16 of the sheet.
3.2. Mixtures
Information not relevant

 

[animeboro]

HCl 37% he use about 11ml to 13ml on 100g 2b4m then he get ph5

 

[William D.]

This is not enough. Here need to check the synthesis or check the quality of the BK4.

 

[abis777]

I don't see any 4mmc precipitate. The color of the mix changes to white or a bit dirty white halfway

 

[dnBQByvHb8Zkawbjpx]

That means there was no 4mmc free base in your mixture, which means no reaction of bk4+MA occurred. I may see your problem - focus on the methylamine above and let's talk details there.