Ethyl Acetate → HCID 54229956, compound

Participants

Reaction Steps

t-Butoxy-bis-dimethylaminomethane (6 cc) is added to a solution of 2-benzhydryloxycarbonyl-7-diethoxyphosphorylamino-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene (10 g) in dry N,N-dimethylformamide (100 cc) at 80° C. After 12 minutes at 80° C., the reaction mixture is poured into ethyl acetate (400 cc) and washed with distilled water (5×250 cc). After drying over magnesium sulphate and evaporation of the solvent under reduced pressure (30 mm Hg; 4 kPa) at 30° C., 2-benzhydryloxycarbonyl-3-(2-dimethylaminovinyl)-7-diethoxyphosphorylamino-8-oxo-5thia-1-azabicyclo[4.2.0]oct-2-ene (E isomer) (10.5 g) is obtained in the form of an orange crystalline solid. This product is purified by crystallisation from ethyl acetate (30 cc), and 2-benzhydryloxycarbonyl-3-(2-dimethylaminovinyl)-7-diethoxyphosphorylamino-8-oxo-5 -thia-1-azabicyclo [4.2.0]oct-2-ene (E isomer) (5.3 g) is obtained in the form of a yellow crystalline powder (m.p.=193°-194° C.).

Provenance & Evidence