Anyone out there having experince in conjugating the TFP ester to benzoic acid ?
I fail many times, TFP is fragile hydrolizing in base condition. And somehow, eventhough we keep the reaction in acid condition, the conjugation reaction still not successfully completed.
I am working on PEG linker and try to conjugate the linker to TFP ester. But, seems like the PEG is hydrophilic and will not easily to keep it binding together with TFP. So, i conjugate the amino benzoic acid at the terminal chain of PEG, with hope that it prevents the TFP from hydrolizing. But, I think it's not work though since I found different peak other than the peak I expected by LCMS.
What should I do ?