反应详情

A mixture of p-nitrobenzyl 7α-azido-3-methanesulfonyloxy-3-acetoxymethyl-cepham-4-carboxylate (0.72 g.), EM silica gel 60 (7.20 g.), and 3:1 PhH-EtOAc (20 ml.) is stirred in a stoppered flask for 4 days at room temperature. The mixture is filtered through a sintered glass funnel to remove the silica gel, which is washed with several portions of EtOAc. Evaporation of the filtrate and washings leaves an oil. This material is chromatographed on Baker silica gel using 9:1 φH-EtOAc as an eluting solvent, to provide p-nitrobenzyl 7α-azido-3-acetoxymethyl-ceph-3-em-4-carboxylate.

1. filtrationThe mixture is filtered through a sintered glass funnel
2. customto remove the silica gel, which
3. washis washed with several portions of EtOAc
4. customEvaporation of the filtrate and washings
5. customleaves an oil
6. customThis material is chromatographed on Baker silica gel using 9:1 φH-EtOAc as an eluting solvent