Talk:Synthesis of NaGHB
Synthesis of NaGHB
NaGHB from GBL and NaOH
Calculations
Measure out the amount of gamma-butyrolactone (GBL) you want to react. (For example: 500ml) Now to calculate the amount of sodium hydroxide (NaOH) needed for the reaction, multiply the amount of GBL in ml by the average density (1.124gr/ml at room temperature).
(500ml) * (1.124gr/ml) = 562gr GBL
Now that we know the weight of the GBL to react, we need to calculate its molecular weight. For that, we take the amount of GBL in gr and divide it by the average molecular weight of GBL (86.06gr).
(562gr) / (86.06gr/mol) = 6.53mols GBL
We need an equimolar amount of NaOH for the reaction. To calculate this we take the molecular weight of the GBL and multiply that by the average molecular weight of NaOH (40.00gr).
(6.53mols) * (40.00gr) = 261.2gr NaOH
And the amount of water (H2O) to use (we preferably have 100ml H2O for 40.00gr NaOH to dissolve in).
(261.2gr NaOH) / (40.00gr NaOH) = 6.53mols (6.53mols) * (100ml H2O) = 653ml H2O
So 500ml GBL requires 261.2gr NaOH and 653ml H2O.
Procedure
NOTE: Only use borosilicate glassware (no plastics, no metal pots, etc). GBL should only be stored in solvent-proof plastics (HDPE 2) or glass containers.
First, measure out 500ml of GBL using a graduated cylinder. In my opinion, it is better to weigh out the GBL so 500ml should be 562gr of GBL. Place the container containing 500ml/562gr GBL aside for now.
Measure out 653ml of (demineralized) H2O, a slight excess is fine here, and add it to a 2000ml beaker.
500ml/562gr GBL requires an equimolar amount of NaOH (261.2gr). Weigh out 261.2gr NaOH, and slowly add it to the beaker.
The NaOH will start to dissolve in the H2O, this is exothermic and will generate quite a bit of heat. Make sure everything is dissolved, and stir for a while with a glass stirring rod.
Once the solution looks clear, start adding the GBL you have measured out earlier in 100gr steps, add slowly, and apply stirring. This is an exothermic reaction as well, generating quite a bit of again. Add the GBL in steps and with stirring. We don't want our reaction to get above 200C, if the temperature gets to 204C or higher you will get a vigorous boil which we want to avoid.
Once all of the GBL is added, let the reaction complete with some occasional stirring. Check the pH which should be 7 (neutral). In case the pH is > 7 just add 10ml GBL, let it react, and check pH again after a couple of minutes. Now it should be 7. If pH is > 7 still, then repeat adding 10ml GBL and letting it react for a couple of minutes and check pH again. If still pH > 7. Then keep repeating this till the pH is 7.
To get rid of any unreacted GBL just boil the solution, let it cool, and solidify. Just add enough H2O to get it back into solution.
You should end up with 822.5gr NaGHB if you used 500ml GBL. The total volume of the solution should be 1153ml in this case. And the solution weighs about 1430gr in total.
You could bring the solution to 150-155C steady boil until no bubbling occurs anymore. And then keep boiling off the remaining H2O to get NaGHB in solid form. If you want a stable solid form of GHB, I would go for Calcium GHB (CaGHB) or Magnesium GHB (MgGHB).
NaGHB from GBL and NaHCO3
Calculations
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Procedure
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