I am trying DCC/NHS coupling for amide bond formation between a small molecule drug and PEG-Amine.
DMSO would be good choice over DCM. DMSO being more polar would dissolve PEG-Amine being and the amide coupling with drug molecule should work well.
However, I suggest you to use DMF instead of DMSO.
In case, you are bounded have difficlty using DMSO or DMF. You can try a small 50 mg batch to see if the coupling is working fine.
In an ideal world, I would use EDCI.HCl/HOBt/DIPEA in DMF for the amide coupling over DCC/NHS.
I hope this helps.
i would not recommend DMSO. This reaction is a water sensitive reaction. DMSO is a solvent that is difficult to get/keep anhydrous.
I did a amide coupling reaction between PEG-amine and a carboxylic acid using dry acetonitrile as solvent.
Greg Petruncio , thank you so much for your suggestions. May I ask how did you remove the reaction by-products?
Greg Petruncio , Thanks again. Can you please share the specs of the column and the protocol for the purification?
It was normal phase silica gel and I purified using 5:1:94 MeOH-NH4OH-DCM
- Badges
- Science topic