反应详情

A solution of methanesulfonyl chloride (0.145 ml, 1.87 mMol) in anhydrous CH2Cl2 (2 ml.) is added dropwise over 10 min. to an ice-cold, stirring solution of p-nitrobenzyl 7α-azido-3-hydroxy-3-acetoxymethyl-cepham-4-carboxylate (0.65 g., 1.44 mMol) and Et3N (0.30 ml, 2.16 mMol) in anhydrous CH2Cl2 (10 ml.). After stirring 15 more min. in the cold, the solution is diluted with ice-cold CH2Cl2 (10 ml.), washed with ice-cold H2O (10 ml.), ice-cold 5% HCl (10 ml.), and ice-cold 5% NaHCO3 (10 ml.), dried with MgSO4, and filtered. Evaporation of the solvent in vacuo leaves p-nitrobenzyl 7α-azido-3-methanesulfonyloxy-3-acetoxymethyl-cepham-4-carboxylate.

1. washwashed with ice-cold H2O (10 ml.), ice-cold 5% HCl (10 ml.), and ice-cold 5% NaHCO3 (10 ml.)
2. dry with materialdried with MgSO4
3. filtrationfiltered
4. customEvaporation of the solvent in vacuo