Description
Diphenyldiazomethane was used industrially for producing benzhydryl esters (diphenylmethyl esters) of β-lactam antibiotics. This “polymeric diphenyldiazomethane” readily reacts with carboxylic acids, e.g. Fmoc-amino acids, which need not to be activated. Products can be cleaved from this very acid-sensitive resin derivative with 1-5 % TFA in dichloromethane. Fmoc-α-amino alcohols can be anchored to PDDM in the presence of BF₃ etherate. As the resulting benzhydryl ethers can be cleaved with 1% TFA/DCM, fully protected peptide alcohols can be obtained.
