反应详情

1.59 g (5.7 mmol) of N-benzyloxycarbonyl-4-hydroxy-L-cis-proline methyl ester are dissolved in 50 ml of abs. pyridine and cooled to 0° C. 0.6 ml (7.7 mmol) of methanesulphonyl chloride is added dropwise at 0° C., and the mixture is subsequently stirred at room temperature for 3 hours. The mixture is then concentrated and 100 ml of methylene chloride are added to the residue, and this latter mixture is then extracted 2 x by shaking with a 10% solution of NaHCO3, dried over sodium sulphate and concentrated once again, with the residue being subsequently distilled repeatedly with toluene. Yield: quantitative Rf : 0.33, eluent, toluene/EtOH (10:1)

1. concentrationThe mixture is then concentrated
2. addition100 ml of methylene chloride are added to the residue
3. extractionthis latter mixture is then extracted 2 x
4. stirringby shaking with a 10% solution of NaHCO3
5. dry with materialdried over sodium sulphate
6. concentrationconcentrated once again, with the residue
7. distillationbeing subsequently distilled repeatedly with toluene