反应详情

3-Methyl-7-(2-phenoxyacetamido)ceph-3-em-4-carboxylic acid (17.75 g., 51 mmoles) was dissolved in 100 ml. methylene chloride. Diphenyldiazomethane (ca. 75 mmoles) was added dropwise with stirring until purple color persisted in the reaction mixture. After an additional 30 minutes of stirring at room temperature, the methylene chloride was evaporated in vacuo. The residue was taken up in a mixture of 100 ml. of water and further processed according to Preparation 4 to yield benzhydryl 3-methyl-7-(2-phenoxyacetamido)ceph-3-em-4-carboxylate [5.03 g.; pnmr (CDCl3 /TMS/delta): includes 2.0 (s, 3H), 3.2 (m, 2H), 4.5 (s, 2H), 6.9-7.6 (m, 11H)].

1. stirringAfter an additional 30 minutes of stirring at room temperature
2. customthe methylene chloride was evaporated in vacuo
3. additionThe residue was taken up in a mixture of 100 ml
4. customof water and further processed according to Preparation 4