nice and efficent route for self 2b4m syntehsis (avg 50 usd a kg)

[Dr. MMX]

Hey i ll just type reagents used by wise choice (price/effort) aviable to buy in europe
so 1st
PCL5 with elemental Sulfur > thionyl chloride

thionyl chloride + propionic acid > priopionykl chloride

4mp synthesis (here is a topicso ill just link):
Propionyl chloride
Toluene
AlCl3 anhydrous

http://bbzzzsvqcrqtki6umym6itiixfhni37ybtt7mkbjyxn2pgllzxf2qgyd.onion/en/threads/synthesis-of-4-methylpropiophenone-from-toluene-by-friedel-crafts-reaction-1kg-scale.209/

somepplecan have problem to brominate it
sulphuric acid that is necesarry to get Hbr that is a bit expensive and not often aviable. Instead we use:
phosphoric acid and NaBh for reactoin > we get HBR
H2O2 12% canbe bought and distilled to some more % like 25-30%

so
4 methylopropione + HBR + h2o2 > 2b4m

i didnt calculate the cost but fery small and no need to wait for shipment or beeing suprised of low quality precursor

 

[chost]

can you explain in more detail how to make HBR?

 

[Dr. MMX]

Oh am really sorry I made mistake. its correct:
To produce hydrobromic acid (HBr) from phosphoric acid (H₃PO₄) and sodium bromide (NaBr), you can use a double displacement reaction. The reaction can be represented as follows:

1. Reactants: Phosphoric acid (H₃PO₄) and sodium bromide (NaBr).
2. Products: Hydrobromic acid (HBr) and sodium phosphate (Na₃PO₄).

The balanced chemical equation for the reaction is:


H3PO4+3NaBr→3HBr+Na3PO4


In this reaction, phosphoric acid reacts with sodium bromide to produce hydrobromic acid and sodium phosphate.

 

[chost]

Is distillation necessary?
And in how much water should I dissolve the sodium bromide?

 

[Dr. MMX]

How otherwise do you plan to get thing that is basicly a gas?

It depends what % youwanna have, max is 47% as I remember and it shouldbe already this way

 

[Benz88]

is it Safe to Distille the h2o2 to maybe 30-35% from 12%?

 

[TheVacuumGuy]

H3po4 with NaBr to produce HBr? Going to try this in a minute.

Got plenty HBr, but just curious if the 2 react.

 

[Dr. MMX]

yes and Na3PO4

 

[Dr. MMX]

thats wonderful

 

[TheVacuumGuy]

Didn't work. I think it would be easier to add sulfuric acid to a solution of KBr (or NaBr) , which would readily yield HBr at 125c

 

[Dr. MMX]

I tried to override having sulfuric acid becasue here is troubles to get it. It was very extreme attempt
if there is access to sulfuric acid its easy job

 

[Dr. MMX]

you can get elemental bromine from potasium bromide, dont need to use acids.
it was quite cheap as i remember

 

[Toddler]

Hbr2 48% can work ?
(CAS.No: 10035-10-6)

how much ration use for bromination
Hbr2
H2O2
for 100g of 4MPP

 

[TheVacuumGuy]

Roughly,

H2o2 50ml
HBr 100ml

 

[Toddler]

for 100g of 4MPP

 

[w2x3f5]

Instead of propionyl chloride, can use propionic anhydride (obtain phosphorus oxide from propionic acid), can also use propionic acid directly with polyphosphoric acid (there are many options for this reaction, you can choose the best one). If propionyl chloride is used with anhydrous aluminum chloride (can be replaced with cheaper and simpler options). Then it is best to carry out a bromination reaction before hydrolysis in Fridel-Crafts (the complex of 2b4m and aluminum chloride is very active for bromination with a high yield).

 

[Dr. MMX]

In chemistry trade buissness in europe propionic acid is considered with "silent restriction" with reason it can be used as biological weapon, so should be avoided there.

very interesting choice of propionic anhydride

 

[Osmosis Vanderwaal]

@TheVacuumGuy you gave him bad figures and he used them and probably ruined 100G 2B4-MP. I dont know what he paid, but I got $200 all day for 10g if it's domestic . In th rules there are a few gold nuggets. "Use the fucking search engine." That's a rule. Another one is " a good chemist i an accurate chemist." Make sure that you clearly state you are guessing when you don't know. You could say nothing at all, you could show your math or you could tell him he needs to figure it himself, but please, dont just throw out random numbers, with no disclaimer.

 

[TheVacuumGuy]

Show me what's wrong then. I used these figures with success. note that hydrogen peroxide is a solution of 35%.

 

[TheVacuumGuy]

i stated roughly , not stoicimeticly

reactants	Coeff	Molar Mass	Moles (g/mol)	Weight (g)
C10H12O	1	148.20168	0,67	100
HBr	1	80.91194	0,67	54,595831842122166
H2O2	1	34.01468	0,67	22,951615663196257
products	1
C10H11BrO	1	227.09774	0.67	153,23560434672535
H2O	2	18.01528	1,35	24,311843158593074

HBr 48% = 8.77 mol/L => for required 0.67m corresponds to 0,0764L (76ml)
h2o2 35% = 11.63 mol/L => for required 0.67m corresponds to 0,0576L (57ml)

Yes that's a bit off from 100 and 50, but these numbers are theoretically, which almost never applies in practice. ( like a mephedrone synthesis is given methylamine x2 but theoretically only needs x1/5 )

furthermore excess reagents are neutralized afterwards.

 

[William Dampier]

Therefore, it is better to control the bromination visually in the reaction of the bromine, because the quality of reagents (especially chinese) can be different. 4mp purity rarely exceeds 95%.

 

[w2x3f5]

The best solution is the preliminary titration of 4MP, then it will be possible to use the correction factor for 4MP

 

[TheVacuumGuy]

.