Question

I posted this yesterday, I was wondering if anyone could still help me...

When doing an acid-base extraction, there are certain rules when chosing the solvent that is to be used in extraction.. one being that it should have a low boiling point. I understand this to be so that the solvent (in this case, ethyl) can be removed rapidly from the compound after extraction without problems.

Can someone further explain why the solvent needs to have a low boiling point? Like, why can't you use dimethylformamide which has a higher boiling point?

Any help would be appreciated. Thanks.

Answer 1

The higher the bp (higher vp), the more compound will vaporize, as it has a vp also.

Answer 2

Hence go for the largest difference in bp that you can get. An added advantage of using a low boiling solvent is that it is more easily removed from the product.

DMF is not good as an extracting solvent as it is miscible with water!