Phosphorus oxychloride → HCID 86738683, compound

Participants

Reaction Steps

Phosphorus oxychloride (1.7 g.), trimethylsilylacetamide (1 g.) and N,N-dimethylformamide (0.73 g.) were added to a suspension of 2-(2-aminothiazol-4-yl)-2-methoxyiminoacetic acid (syn isomer, 1.8 g.) in tetrahydrofuran (20 ml.) at 5° C. Thus obtained solution was added all at once to a solution of 4-nitrobenzyl 7-amino-3-acetoxymethylenecepham-4-carboxylate (2.9 g.) and trimethylsilylacetamide (5.4 g.) in tetrahydrofuran (30 ml) at -20° C., and the mixed solution was stirred at -10° to -15° C. for an hour. After adding water (10 ml.) at -30° C., the resultant mixture was poured into a solution of ethyl acetate (200 ml) and water (200 ml.), and adjusted to pH 7.5 with sodium bicarbonate. The organic layer was separated, washed with a saturated aqueous solution of sodium chloride and treated with activated charcoal. After concentrating the solution under reduced pressure, the residue was pulverized with diisopropyl ether and collected by filtration to give 4-nitrobenzyl 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-acetoxymethylenecepham-4-carboxylate (syn isomer, 2.7 g.).

Provenance & Evidence