Hello!

I would like to do a DCC coupling of PMAA (100 kDa) with an amine. I already found a paper where they dissolve PAA in NMP under stirring at 60 °C for 24h. In my case I need to use PMAA instead of PAA but it didn't dissolve very well in NMP - the solution is very turbid and there is a small precipitate at the bottom of the flask. I can't use water because DCC doesn't dissolve in it. I also tried the synthesis with EDC HCl in a mixture of THF/H2O but it didn't work well so that I would like to switch to DCC instead. Here PMAA dissolved very well. Shall I also give several amounts of HOBt to the reaction mixture to get a better yield?

In the current paper they dissolve the coupling agent as well as the amine in NMP before adding to the reaction mixture whereas in the other paper containing the EDC coupling reaction they add both compounds to the dissolved polymer directly. Is there any difference? Interestingly, none of them used HOBt.

Thanks in advance.