[darkdevil]

Dear all,

I have a question about how to remove the acid after the amidation reaction. I used an excess of acid chloride for the amidation. And afterwards I washed many times with water and a base (sodium bicarbonate). I then did a flash chromatoography to get my product. The TLC showed a single spot, but the final product is a sticky gel, with the smell of my acid which i recognize it is the acid I used as starting material.

 Repeating the extraction process with the base does not seem to work. I suppose the product is a powder, while I did the same reaction to a similar compound, except this one has 2 bromine groups.

I wonder what I have done wrong?? Any help would be greatly appreciated. Thank you!

[discodermolide]

Some acid chlorides are remarkably resilient to hydrolysis. You don't mention which one you used.
Perhaps use dilute NaOH to remove the excess acid chloride.

[Babcock_Hall]

Can you use the free acid or the acid chloride as TLC standards?

[darkdevil]

I used Hexanoyl chloride.

[darkdevil]

Some acid chlorides are remarkably resilient to hydrolysis. You don't mention which one you used.
Perhaps use dilute NaOH to remove the excess acid chloride.

I tried to use diluted NaOH to remove the acid , but the amide is easily hydrolyzed..

[discodermolide]

How easily? What happened to the product?
It should survive dilute NaOH at rt. Or do the extraction at 4°C.

[orgopete]

If you cannot remove excess acid chloride, use less acid chloride. It may be easier to recycle recovered amine.