In solid phase synthesis, if I use HOBt in situ, does the excess of HOBt make any problems in coupling step?

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Laurent F Bornaghi

Dear Samira, I have limited experiences but never had any problem with excess HOBT when doing solid phase pep. synthesis

Have a look at this, could be of interest:

http://www.chempep.com/ChemPep-Fmoc-Solid-Phase-Peptide-Synthesis.htm

Luigi Grassi

The only trouble is that it is difficult to remove by simply washing the mixture when performing synthesis in solution, but for the reaction itself what is dangerous it the use of less free amine then EDC or any carbodimide.