Phosphorus oxychloride → 4-Nitrobenzyl 7-[2-(2,3-dihydro-1,4-oxathiin-6-yl)-2-n-propoxyiminoacetamido]-3-chloro-3-cephem-4-carboxylate

Participants

Reaction Steps

A solution of 4-nitrobenzyl 7-amino-3-chloro-3-cephem-4-carboxylate hydrochloride (5.0 g.) and trimethylsilylacetamide (11.3 g.) in dry ethyl acetate (100 ml.) and a solution of 2-(2,3-dihydro-1,4-oxathiin-6-yl)-2-n-propoxyiminoacetic acid (syn isomer, 3.13 g.), dry N,N-dimethylformamide (1.13 ml.) and phosphoryl chloride (1.33 ml.) in ethyl acetate (54.4 ml.) were treated in a similar manner to that of Example 19-(1) to give 4-nitrobenzyl 7-[2-(2,3-dihydro-1,4-oxathiin-6-yl)-2-n-propoxyiminoacetamido]-3-chloro-3-cephem-4-carboxylate (syn isomer, 7.10 g).

Provenance & Evidence