摘要:
The synthesis of the (alpha,alpha-difluoroalkyl)phosphonate analogue of L-phosphoserine, 5, in a form appropriate for solid phase peptide synthesis, is reported. Two independent routes are described, starting from L-serine or (R)-isopropylideneglycerol. In each case, PCF2-C bond formation is achieved by triflate displacement with diethyl lithiodifluoromethylphosphonate.