Sulfuric acid magnesium salt (1:1) → Benzhydryl 7beta-(2',3'-dibromo-2'-ethylbutylideneamino)-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylate

Participants

Reaction Steps

To a solution of benzhydryl 7β-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylate (2.47 g, 5.00 mmol) in methylene chloride (35 ml) was added under ice-cooling a solution of 2,3-dibromo-2-ethylbutanal (1.42 g, 5.50 mmol) in methylene chloride (5 ml) followed by addition of anhydrous magnesium sulfate. The resulting mixture was stirred at room temperature for 4 hours. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure and, after addition of benzene (20 ml) and thorough stirring, insolubles were filtered off. The filtrate was concentrated to dryness under reduced pressure and the reside was made powdery by the addition of ether (10 ml). The resulting powder was recovered by filtration and dried under reduced pressure to give 3.12 g (85%) of the title compound as a pale brown powder.

Provenance & Evidence