AMPHETAMINE via ELECTROLYSIS in divided CELL

[Eleusius_hive_reboot]

ELECTROCHEMISTRY RESEARCH
[DOCUMENTATION | METHODOLOGY ]



Amphetamine Synthesis
» for the skilled Chemists ONLY !

Phenyl -2-nitropropene
Ectrolytic Reduction Method
high yield / less hazards
___________________________________

exclusively compiled for:

“THE BB.GATE“
[ Educational Content ]


Special thanks and dedication to G.Patton !
================================

Introduction​

This experimental procedure describes the electrochemical reduction of phenyl-2-nitropropene to racemic amphetamine, followed by workup and isomeric separation to obtain the eutomeric dextro isomer. The final product is isolated in the form of the mono-basic phosphate salt, which is the stable form of the compound.

Materials and Setup​

• Starting Material: Phenyl-2-nitropropene.
• Electrolyte Solution: A mixture of ethanol (EtOH) and aqueous acetic acid (AcOH), and aqueous sulfuric acid (H₂SO₄).
• Cathode: Spongy lead-superoxide electrode.
• Anode: Spongy lead electrode.
• Electrolytic Cell: Divided setup with a red terracotta cathode compartment and an HDPE box for the anode.
• Power Supply: DC lab power supply with adjustable current and voltage.
• Temperature: 40°C.
• Final Product: Racemic amphetamine, isolated as the mono-basic phosphate salt.

Experimental Procedure​

1. Preparation of Cathode Compartment:
   • The cathode compartment is constructed using unpainted red terracotta, chosen for its favorable ion-permeability properties. The material is treated overnight with dilute sulfuric acid to enhance electron transfer properties.
   • The cathode itself is a spongy lead-superoxide electrode, selected for its ability to support the required reduction reaction.
2. Preparation of Anode Compartment:
   • The anode compartment is set up using a larger HDPE box, containing a spongy lead anode. Aqueous sulfuric acid is used as the electrolyte.
   • The anode and cathode are placed in parallel positions to ensure uniform electric field distribution.
3. Electrolyte Solution:
   • Phenyl-2-nitropropene (the starting material) is dissolved in a solution of ethanol (EtOH) and aqueous acetic acid (AcOH). The acetic acid concentration is maintained at approximately 10-15% by volume, which provides the necessary acidic environment for the reduction.
   • Aqueous sulfuric acid (H₂SO₄) is used as the supporting electrolyte in both the cathode and anode compartments. The concentration of sulfuric acid in the cathode compartment is kept at around 2 M, while the anode compartment contains a 1 M sulfuric acid solution.
4. Electrolytic Reduction:
   • A DC power supply is connected to the electrolytic cell, and the voltage is set to a constant 4.5 V with the current adjusted to 0.5 A for optimal reduction conditions.
   • The system is maintained at a constant temperature of 40°C, ensuring that the reaction runs smoothly and efficiently.
   • The reduction is conducted until 8 Faradays have been passed, which is calculated based on the charge required for the complete reduction of the nitro group to the amine.
5. Workup Procedure:
   • Upon completion of the electrolysis, the reaction mixture is extracted using an organic solvent, such as dichloromethane (DCM), to separate the organic products from the aqueous phase.
   • The organic layer is then washed with water and dried over anhydrous sodium sulfate (Na₂SO₄).
   • The solvent is evaporated under reduced pressure to yield a crude product.
6. Isomeric Separation:
   • The crude racemic amphetamine isomer mixture is subjected to chiral resolution methods to separate the eutomeric dextro isomer from the levo isomer. A common method involves the use of chiral chromatography or the formation of diastereomeric salts.
   • To isolate the eutomeric dextro isomer, a suitable chiral resolving agent, such as tartaric acid, can be used to form diastereomeric salts. These can be separated by recrystallization.
   • Once the eutomeric dextro isomer is isolated, it is purified further through recrystallization to ensure high purity.
7. Formation of Mono-Basic Phosphate Salt:
   • The purified dextro isomer is then reacted with phosphoric acid (H₃PO₄) to form the stable mono-basic phosphate salt. The reaction is carried out in a suitable solvent, such as ethanol or acetone, under mild conditions to avoid degradation of the product.
   • The salt is then isolated by evaporating the solvent, and the solid product is recrystallized from an appropriate solvent to obtain pure mono-basic phosphate salt.

Conclusion​

The electrochemical reduction of phenyl-2-nitropropene to racemic amphetamine was successfully achieved in a divided electrolytic cell. The product was then subjected to isomeric separation to isolate the eutomeric dextro isomer. The final stable form of the compound was obtained as the mono-basic phosphate salt, which provides a stable and purifiable product suitable for further application or use.


+++++++++++++++++++++++++++++++++++++
THIS IN DEPTH WORK was carried out in 2014
*****************************************
AND RESULTED IN SUCCESS

REPRODUCEABLE,
HIGH YIELDING

EXPERIMENTATION .

PRODUCT OBTAINED;
WAS OF SOPHISTICATED
PURITY PROFILE…… !!!

THANKS FOR READING:

 

[G.Patton]

Hello. Thank you for your report. Can you answer following questions?
For a what amount of P2NP?
What is a yield?
how much of each reagent?
Can you also supply exactly amounts and description of these procedures please?

 

[Eleusius_hive_reboot]

Sure:

I carried out multiple scale Operations back then,

from nano- Testruns in the beginning...

which Climaxed then to 4 Apparatuses ( DC POWER supplies & Vessels)
running simultaneously with ~60g P2NP each -day and night...

the yield in this manufacturing adventure
obtained a 70 % ratio each run
(Sulfate Salt, Racemate )*


Sweet Spot setting with over 80 % product was
gained by loading the MACHINE
with 35g P2NP Catholythic Solution
________________________________________________________________
* the product was the racemic sulfate Salt back then,
but i explored chirality and alternative salt ... out of
curiosity....
-------------------------------------------------------------------
ANYWAYS -- HERE IS THE
REFERENCE / eXAMPLE
X-PERIMENT , THE BLUEPRINT
(written to be easy scalable /
i think you`ll see how i mean...)

Procedure​

1 mol (164 g ) of phenyl-2-nitropropene, C6H5CH=C(CH3)NO2, is dissolved....
in to a solvent MIXTURE prepared

by mixing 1000ml of EtOH with
500ml of acetic acid (80%) and
500ml of 12 N sulfuric acid. T

the homogenously stirred,
slightly warmed up solution
(Completely dissolve,
no suspending Material should be left !)

next STEP:
pour Mixture slowly in to the
_______________________________________________________________________
cathode compartment:

A Terracotta-Pot >> un painted / withoud bottom Hole

pre treated by sandpapering the surface /

pre soaked w.H2SO4 -5% conc. overnight

attached with "Bottle Neck " sealed with Teflon Tape /

groundglass gas venting adaptor- Olive /
Aquarium Tube with A BALLOON Attached

[ pour a spatula heap of finely divided active C in to The Catholytic Mix ]

NOW set in PLACE:
cathode of Spongy PbO2.
-------------------------------------------------------------------------
Anode Compartment / >>the outer Vessel
(the Cathode Pot Placed Inside THIS CONTAINER,OK?)

>> HDPE Cannister with cutoff Top,
performed great !

same source of ELECTRODE [but the Pb one]
as ANODE,

-- suporting anolyte = 12N H2SO4...
Cell was Filled with Anolyte Until reaching same Level
as liquid in the Cathode-Pot...
-----------------------------------------------------------------------------
The Hole SETUP WAS PLACED IN A WATER BATH
standing on top of PROFESSIONAL MAG-STIR w. Heating...

Current is passed, using a current density of ~0.2 A/cm2 of cathode surface.
The temperature is kept at about 40°C during the electrolysis .

When eight Faradays of electricity had passed.
( i dont remember exact duration but i think around 12 Hours)

When the reduction is completed,
get rid of ethanol and ethyl acetate thats present via evaporation.

add 100mls of NON POLAR SOLVENT
(<i usd.TBME )
on to the now chilled remaining acidic solution solution.

Alkalize to PH 13 by addition of conc./ cooled NaOH Solution .
the desired amphetamine freebase is then subsequently,
extracted with
two additional portions of Tert-butyl-methyl-Ether.
(or what you prefer instead as NP)

the solvent was distilled off by short way vacuum
distillation.
the Freebase remaining was pale yellow oily substance
[like described in litrtre.. / with characteristic Amine Odour ]
which i had
dried over KOH in Vacuum Dessicator Over Night
weighed the next day---
60 % Yield (Freebase)
from 1mol Nitroalkene

IMPORTANT NOTE:
The H2 Gas coming from Cathode compartment
should be vented out by pipe tubings, because of dangerous
HHO Formation with the Anodic Vapours !

-> !!! I ended up with cutting the Bottom of a Lemonade Bottle
and attached it to the Terracotta Pot / Sealed it with teflon Tape,
drilled a small hole under the bottle neck to insert the crocodile clamp for
fixation of PbO2 Cathode / a gas outlet adaptor for groundglassware with a few cm
aquarium tube attached
holding a common Latex Ballon attached - collecting nascent H2.../
recognized that this was enhancing as f**k ...
from then-- powdered active-carbon was
sprinkled in Catholyte...to re -absorb Hydrogen !

SOURCING OF ELECTRODES :

The Electrodes that worked superbly, were taken out of a 12v - moped-battery - a new bought
without the including acid infused of course.

those Pb Anode / PbO2 Cathodes made of spongy Lead are already PERFECT !


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Journey from a decade ago