This is a discription ho to yield anhydrous ethers.
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1. evakuate the reaktion apparature through vakuum1.
2. add Ar in the apparatur via valve1 and add THF and Na into the lower vessel.
3.Add a bit Benzophenone to the lower vessel.
4. Reflux till u see a blue color in the lower vessel .
5. Close the left valve and wait until enough THF is in the upper vessel.
6. valve 1 is closed and evakuated via vakuum2.
7. if enogh solvent is present in the upper vessel vakuum2 is stopped and valve1 is opend so that freshly destilled solvent is let to the flask .
8. gas Ar through the flask with the freshly destilled THF.
9. Ready. U have THF with ~10ppm Water