反应详情

To a solution of 0.483 g (3.0 mmoles) of diethylaminosulfur trifluoride in 10 ml of CH2Cl2 at -78° under N2 was added a solution of 1.61 g (3.0 mmoles) of benzhydryl 3-hydroxymethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate-1-oxide in 50 ml of CH2Cl2 and the mixture was stirred at -78° for 0.5 hr, then poured into 100 ml of water. The CH2Cl2 layer was dried (MgSO4) and evaporated in vacuo. The residue was chromatographed on silica gel with 9:1 CH2Cl2 -acetone to yield 0.095 g of benzhydryl 3-fluoromethyl-7-(2-thienylacetamido)-3-cephem-4-carboxylate-1-oxide in fractions 12-15, rf = 0.60 on tlc with 9:1 CH2Cl2 -acetone; mp 205.5°-207.5° d; ir (CHCl3) 3450 (amide N--H), 1805 (β -lactam C=O), 1725 (ester C=O), 1680 (amide C=O), 1495 ("amide II" band), and 700 (aromatic) cm-1.

1. dry with materialThe CH2Cl2 layer was dried (MgSO4)
2. customevaporated in vacuo
3. customThe residue was chromatographed on silica gel with 9:1 CH2Cl2 -acetone