Author Topic: Grignard imine meth production workup  (Read 3499 times)

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4k4r3

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Grignard imine meth production workup
« on: November 01, 2003, 06:46:00 PM »
Chemicals:
Toluene
Formaldehyde 36%
Ammonium chloride
Potassium dichromate .05mol
Some acid (HCl 36%, H2SO4 5mol)
95% Ethanol (Methylated Sprits)
Ether (Starting Fluid, aerostart)
Slica Gel (Little white packets)

These not-me will use to create Benzyl Chloride, Methylamine.HCl and Acetaldehyde using the respective methods; Photo-Catalysed Chlorination of Toluene, Condensation product of Formaldehyde and Ammonium chloride and partial oxidation of ethanol to Acetaldehyde and the subsequent conversion to the ammonia trimmer. After proceeding to make these lovely ingredients not-me will use the Gazz Italia method to hopefully produce 40% yields. Any input would be appreciated.

WorkUp:

Part 1: Methylamine.HCl (1)
1.   Add 250g Ammonium Chloride to 500g formaldehyde (36% w/w)
2.   Heat until exothermic reaction kicks in at bout 90°C then cooling is applied to keep the temperature below 105°C
3.   When reaction slows down remove cooling and maintain temperature at 105°C for 30-90min
4.   Turn up the heat and boil off water until ammonia chloride crystals start to form, cool filter off crystals.
5.   Continue to heat until free of water (indicators?)
6.   Extract with hot ethanol, filter hot. Repeat several times.
7.   Concentrate then allow Methylamine crystals precipitate at room temp then fridge -> freezer.
8.   Filter. Repeat

Part 2: Acetaldehyde
1.   I’m not going to bother writing it up it’s just

https://www.thevespiary.org/rhodium/Rhodium/chemistry/acetaldehyde.html

(great site Rhodium)

Part 3: Photo Catalysed Chlorination of Toluene
1.   One again just the reaction from Rhodium’s site

https://www.thevespiary.org/rhodium/Rhodium/chemistry/benzylchloride.html



The Reaction: Benzylmagnesium chloride alkylation of acetaldehyde methylimine to give Meth
This will be preformed according to Gazz Chim Italiana (2)
1.   The reaction will proceed thus,
2.   Gas Methylamine into ice cold ether (dried with silica gel). Weight to find out concentration of methylamine gas absorbed. Add the equi molar amounts of Acetaldehyde, plus more silica gel to remove water, Stir for ~5min and then decant solution into separatory funnel place over cooled preprepared benzylmagnesium chloride. Slowly combine ice cold sol with siting. Reflux for 2 hours, cool. Then distil off ether, heat residue on steam bath for 2 hours, cool. Add enough ether to dissolve mixture then add ice + dilute Sulphuric acid to hydrolyse. Wash repeatedly with ether basify, then steam distil. The distillate is acidified with HCl and concentrated dry. Dissolve in minimal ethanol then precipitate with the addition of ether.

Sooo, what do the other bees think about the method, it it workable? Also one question about Benzyl Chloride synth; what is the best way to separate the Benzyl Chloride from the waste products? The only vacuum source not-me has is a (homemade) water aspirator and not-me’s thermometer only goes to 110°C. Anyway most of this stuff was pilfered off Rhodiums site, big up to Rhodium for that one. Also if there is any easier method of producing the precursors not-me is very much interested, not-me TFSE’d around a bit and came across Cu catylazed production of acetaldehyde from ethanol and water vapour, however it looks a little complex (two boiling flasks connected by some sort of y adaptor) plus the catalyst has to be at 300 °C so it’s a little impractical in not-me’s situation. Also is silica gel a suitable drying agent? Not-me understands that it has to be pre dried first say 2 hours at 200°C, is this correct? Any way thanks for everything, The Hive has already become a great resource for not-me.

Refs
1.

https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylamine.html

and

https://www.thevespiary.org/rhodium/Rhodium/clandestine/methylamine/index.html


2. The Grignard reaction -

Post 202649

(Rhodium: "Meth via grignard rxn (Gazz Chim Italiana)", Novel Discourse)

3. Plus some others I can’t really remember

hypo

  • Guest
grignard
« Reply #1 on: November 02, 2003, 12:50:00 AM »
at least spell the poor man's name right...