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Old Mar 27th 2019, 06:52 PM   #1
JesseChem
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I need help!

Hello, I am in the process of creating pentobarbital. 100$ scientific purposes. Seeing how everything reacts etc. However i am stuck. Here is the procedure i am following.

1) A hotplate was rested on the base of a
clampstand. A cooking pot containing 400 g of
anhydrous (dry) ethanol is placed on the
hotplate stirrer and 26.7g of clean metallic
sodium is dissolved in it.

2) Into the stainless steel cup there is placed a
Solution of 100 g of l-methy] buty]-ethy]
malonic ester(Propanedioic acid). The cup is
then placed into the small cooking pot
containing a mixture of the Ethanol and Sodium
and secured with clamps to the clamp stand.
The end of the thermometer is placed in the pot
and positioned as close to the cup as possible.

3) it is warmed to a temperature of 170'C for IO
minutes to remove any residual moisture.
Throughout the reaction the temperature of the
mixture is kept at 170C and stirring is done
frequently.

4) 10.9 of urea is added slowly, one scoop at a
time and with good stirring. During this moisture (water) formed making the mixture
damp. Over the course of 20 minutes the
mixture gradually dries out and the amount of
released gas lessens.

5) Another 10.9g of urea is added and allowed t-
react for 35 minutes.

6) The last 10.9 of urea is added and allowed ti
react for 30 minutes.

7) After adding the total amount of urea over 1h
25 min, the mixture is dry, contained yellow
and off-yellow-to-white granules, and still
damp with the water and alcohol. The product i
then heated at a temperature of 280'C directly
on the hotplate for 1h 20mins. During this
process the mixture is stirred every 15 minutes
and off-yellow-to-white granules became
more prominent and as yellow ones lessened.
The precipitated product is washed with cold
water , filtered and heated again for about 40
minutes at a temperature of 127-130'C until all
the water is removed and the white
powder(Nembutal Sodium) is formed .

However i am stuck at step 4. Do i add the urea to the steel cup containing the malonic acid, or do i add it t9 the ethanol and sodium metal mixture? And what is the purpose of the malonic acid in the seperate steel cup? Is it for a non direct reaction, and after its done, will the malonic acid disappear? Or do i add it to the sodium mixture or discard it? The procedure was not bery helpful! Thank you
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