[AlphaScent]

I have over shot with base and fear my ester has saponified and is in the aqueous layer.  If I acidify to ph > 2 and try to extract.  Do you think anything will come out?  Use ethyl acetate over hexanes or ether?  Has anyone had to do this before?  My compound is 4,6-octadienoic acid. 

I have never had to do this.  In theory it should work. But that hydrogen bonding makes me think it could be difficult.

Cheers

[discodermolide]

Use toluene, extraction should be ok.

[Babcock_Hall]

We have purified (iso)nicotinate derivatives of BOC-ornithine and BOC-lysine by first extracting them into an aqueous layer.  They we lower the pH and extract them into ethyl acetate.  I don't think our recovery is great, but it does seem to work.

[kriggy]

I have over shot with base and fear my ester has saponified and is in the aqueous layer.  If I acidify to ph > 2 and try to extract.  Do you think anything will come out?  Use ethyl acetate over hexanes or ether?  Has anyone had to do this before?  My compound is 4,6-octadienoic acid. 

I have never had to do this.  In theory it should work. But that hydrogen bonding makes me think it could be difficult.

Cheers

just to be clear, the product you want is acid or ester?
I did this with pyridine-2,6-dicarboxilic acid methyl ester.
Neutralize unreacted acid with Na₂CO₃ till basic pH, then extract with chloroform, dry, evaporate. Yields over 85% (usualy 95%+)