反应详情

Trifluoroacetic acid (20ml) was added slowly to a mixture of anisole (5ml) and diphenylmethyl 3-carbamoyloxymethyl-7β-[2-methoxyimino-2-(fur-2-yl)acetamido]-ceph-3-em-4-carboxylate (syn isomer) (4.7g, 8 mmole) which had been cooled in an ice-bath. The flask was shaken occasionally during the next 10 minutes to ensure complete solution of the solid. It was then removed from the ice-bath and excess trifluoroacetic acid was removed on a rotary-evaporator. Trituration of the residue with ethyl acetate (5ml) gave 3-carbamoyloxymethyl-7β-[2-methoxyimino-2-(fur-2-yl)acetamido]-ceph-3-em-4-carboxylic acid (syn isomer) (3.3g, 94%) as a solid which was filtered off and washed with diethyl ether.

1. temperaturehad been cooled in an ice-bath
2. customIt was then removed from the ice-bath and excess trifluoroacetic acid
3. customwas removed on a rotary-evaporator