V-Fmoc deprotection reaction

In synthesizers operating in the batchwise mode of synthesis, monitoring of the deprotection reaction is carried out by taking aliquots and measuring the change over time of the optical density or conductivity of the sample. 

Whilst deprotection with piperidine is effective in most cases, it has been shown that for long peptides incomplete Fmoc deprotection can occur even in 

Anhydride, generated in DCM, but used in OMF. Wastes 1 eq. of amino acid derivative. 

Fmoc-amino acid/DICf HOBt(1 1 1)inOMF 

Fmoc-amino acid/HATU/ DIPEA(1 1 2)inDMF 

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