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+ Drying
+ Potassium
+ Organic chemistry
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Krister Sundelin

How to dry potassium tertiary butoxide?

Declining USA  Follow

Solid KH in paraffin is preferred over KH in mineral oil. It is stable in air and can be used to prepare active t-BuOK as required.
Article Potassium Hydride in Paraffin: A Useful Base for Organic Synthesis



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Bryan Foong Zhi Chuan  Follow

Potassium t-butoxide is commercially available as a solution and as a solid, but it is often generated in situ for laboratory use because samples are so sensitive and older samples are often of poor quality. It is prepared by the reaction of dry tert-butyl alcohol with potassium metal.[1] The solid is obtained by evaporating these solutions followed by heating the solid. The solid can be purified by sublimation at 220 °C and 1 mmHg.

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David Garcia  Follow

Try to use dessicator with P2O5 and vacuum.

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Ben Jones  Follow

It is its own best drying agent, which, unfortunately, is self consuming. Like milk, buy only as much as you need with short-term storage in a dessicator. 

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Adam Jacholkowski  Follow

Great, thank you all above.

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Omme Salma   Follow

As others have suggested, your best bet is to buy a pure sample and make sure you treat it under strictly anhydrous conditions.  If you have some material already and you need a pure sample, Carlos above is correct that you can remove t-butanol under vacuum and heat, but that will leave KOH.  If that is a problem, one of the tips in this link tells you how to purify small amounts of KOtBu:   https://chemtips.wordpress.com/tag/potassium-butoxide/

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Abdullah  Follow

If you're have to keep potassium t-butoxide then use potassium metal in a sure-sealed bottle under dry inert atmosphere (argon or helium). Use only double-ended needles (cannula) with the help of dry argon/helium gas to transfer the exact amount you require.

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Clive Holloway  Follow

useful

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Ahmad Zahir  Follow

Why do you need to struggle keeping potassium t-butoxide dry while you can generate it in situ and use it immediately.

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Angel Wallace  Follow

Potassium tert-butoxide readily reacts with humidity. You can heat potassium tert-butoxide at ~155 ºC, in vacuum (approx. 2 mmHg), for about 1 h, to evaporate any tert-butanol possibly present as impurity.

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Mohamed Garnett  Follow

tBuOK is well soluble in THF (25g/100g@25oC) but KOH and K2CO3 are not. Dissolve-> filtrate->evaporate to dryness - simple and highly efficient method. tBuOK build complex with tBuOH (!) , but it destroyed below of thermal stability temperature of tBuOK (~ 250°C ) .
Vacuum sublimation is good but complex and low productivity method.

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Dexter Haven  Follow

Potassium t-butoxide is commercially available as a solution and as a solid, but it is often generated in situ for laboratory use because samples are so sensitive and older samples are often of poor quality. It is prepared by the reaction of dry tert-butyl alcohol with potassium metal.[1] The solid is obtained by evaporating these solutions followed by heating the solid. The solid can be purified by sublimation at 220 °C and 1 mmHg.

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