p-Toluenesulfonic acid monohydrate → 3-Acetonyl-7-amino-2-benzhydryloxycarbonyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene

Participants

Reaction Steps

A solution of p-toluenesulphonic acid monohydrate (3.8 g) in acetonitrile (50 cc) is added, in the course of 30 minutes, to a solution of 3-acetonyl-2-benzhydryloxycarbonyl-7-t-butoxycarbonylamino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene (5.23 g) in acetonitrile (50 cc) at 40° C. The mixture is kept at 40° C. for 30 minutes and then concentrated under reduced pressure (20 mm Hg; 2.7 kPa) at 40° C. to a volume of about 30 cc. It is diluted with methylene chloride (150 cc) and the solution is washed with a saturated aqueous solution of sodium bicarbonate (50 cc) and dried over magnesium sulphate. This yields a solution of 3-acetonyl-7-amino-2-benzhydryloxycarbonyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene, which is identical to the product described in Reference Example 2.

Provenance & Evidence