[Nescafe]

Hi,

I have made a compound which is reported in literature as a white solid. Yet I noticed after purification my material is an orange oil with a small impurity that is hard to separate. So I started to try crashing my stuff out. Noticed that both product and impurity are DCM soluble with the product being very slightly soluble in Hexanes while Impurity is totally insoluble in hexanes. So after adding a mL of DCM I added 9mls of Hexanes and saw that the orange impurity stayed at the bottom of the vial like a big orange ball while the hexane solution was cloudy. Filtered what I could but when I analyzed the precipitate and filtrate there is product in both. I think product and impurity have similar polarities, what would be the next best move? Should I try ether instead of hexanes hoping that my product has better solubility in ether v.s. Hexanes?

Thanks in advance,

Nescafe.

[phth]

Sounds good for a dual solvent crystallization.  Put some extra DCM in there, figure out when it precipitates out, adjust the conditions by adding more DCM, and stick it in the fridge.

[tomek]

What about chromatography. See if your colored impurity can be retained and the product eluted. Then simple filtering through a plug of silica should do the job.