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Topic: drying agents  (Read 3746 times)

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Offline km

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drying agents
« on: March 10, 2011, 06:10:38 PM »
Why would you use anhydroous potassium carbonate as a drying agent instead of anhydrous magnesium sulfate in an experiment?
For example in a Petasis reaction (Boronic acid Mannich reaction) where the product is benzyl methylcinnamylamine why would you use potassium carbonate instead of magnesium sulfate to dry the organic layer?

Offline enahs

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Re: drying agents
« Reply #1 on: March 10, 2011, 07:27:05 PM »
Usually they are pretty interchangeable. There are some solvents though that some drying agents might be slightly soluble in.

Offline Honclbrif

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Re: drying agents
« Reply #2 on: March 10, 2011, 09:15:01 PM »
Mg cation has not inconsiderable Lewis acidity. Sometimes if you try to dry amines over them, you lose quite a bit of product. If you're trying to dry a basic species, K2CO3 is usually a pretty good way to go.
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