HCID 67673832, compound → HCID 58430309, compound

Participants

Reaction Steps

A solution of 194 g (0.52 Mol) of (6R, 7S)-7-tert-butoxycarbonylamino-3-hydroxy-methyl-8-oxo-1-aza-bicyclo[4.2.0]-oct-2-ene-2-carboxylic acid tert-butyl ester (9) in 4.85 l of methylene chloride was stirred with 455 g (0.52 Mol) manganese(IV) oxide at 22-25° C. for 15 h. Another 45.5 g manganese(IV) oxide was added and stirring was continued for 24 h. A further 45.5 g of manganese(IV) oxide was added and stirring was continued for 3.5 h. The solids were removed by filtration over 500 g dicalite and washed with 3 l methylene chloride. The combined filtrates were concentrated under aspirator vacuum and dried at 0.1 torr at 40° C. The residue was dissolved in 182 ml methylene chloride, diluted with 730 ml of pentane and stirred at room temperature for 30 min. The resulting solid was collected by filtration, washed with 140 ml pentane and dried at 0.1 torr at 40° C. to yield 158.5 g (6R, 7S)-7-tert-butoxycarbonylamino-3-formyl-8-oxo-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid tert-butyl ester (10) as colorless crystals (83% Th.); m.p.: 194-195° C.

Provenance & Evidence