I am trying to synthesize a compound that contains a carboxylic acid to form a secondary amide by using pivaloyl chloride and methylamine in DCM solution. Are there any articles that anybody can send to me?
This should not be a problem: Make reaction in DCM in a ratio of 1 eq of pivaloyl chloride and 2.1 eq of methylamine, formed methylammonium chloride to extract by water.
Dr Pazdera's procedure will work - however the yield might be moderate. I might be inclined to try a Schotten-Baumann reaction. Add the amine (slight excess) and the acid chloride via syringes (slowly) into a stirred vessel with containing a little water (over ice) and a pH probe. When the pH goes over 9 .. add 2M NaOH ( another syringe) to hold it to pH 8-9. At the end of addition, stir for a few hours then extract with DCM. This worked for us with a lot of difficult substrates. Best wishes.
For the Schotten- Baumann we modified the procedure described in JP Greenstein's 'The Chemistry of the amino acids' Ca 1983... can't remember the volume. We used it for preparation of secondary amides from N-acetyl amino acids and a number of amines. I don't have our references to hand.. sorry. If you get to much hydrolysis of your acid chloride .. try using THF-water at the start.
Schotten-Baumann procedure is not usable for chlorides or anhydrides of aliphatic carboxylic acid because their hight reactivity. For aromatic or sulfochloride (but not MeSO2Cl, CF3SO2Cl and similar hight reactive).
For inspiration see http://www.organic-chemistry.org/abstracts/literature/876.shtm
I was checking out the article and I did not see a reaction scheme where it is going from a carboxylic acid to form a secondary amide.
For many method for amide formation see
http://www.organic-chemistry.org/synthesis/C1N/amides.shtm
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