Phosphorus trichloride → Diphenylmethyl 7-(2-thienylacetamido)-3-(1-acetoxyethyl)-3-cephem-4-carboxylate

Participants

Reaction Steps

To a cooled solution of 0.514 g. of benzhydryl 7-(2-thienylacetamido)-3-(1-acetoxyethyl)-3-cephem-4-carboxylate 1-oxide (isomer II from the previous example) in 15 ml. of dimethylformamide was added 0.190 ml. of phosphorous trichloride. The reaction mixture was removed from the ice-bath and allowed to warm to room temperature at which temperature it was stirred for one hour. The reaction mixture was then transferred with the aid of ethyl acetate to a separatory funnel and was then washed with aqueous sodium bicarbonate solution (2X), and brine (2X) and then dried over anhydrous sodium sulfate. Evaporation in vacuo provided a product which was chromatographed on a silica gel column using a toluene-ethyl acetate gradient to give 0.328 g. (65.5 percent) of the title product as a froth:

Provenance & Evidence