Sodium Iodide → HCID 70507474, compound

Participants

Reaction Steps

3-Methyl-7-(5-methyl-3-phenylisoxazole-4-carboxamido)ceph-3-em-4-carboxylic acid (25.9 g., 65 mmoles) was dissolved in anhydrous dimethylformamide (150 ml.). Triethylamine (19.7 g., 195 mmoles), potassium bicarbonate (19.5 g., 195 mmoles), sodium iodide (29.3 g., 195 mmoles) and chloromethyl pivalate (29.3 g., 195 mmoles) were added. An exotherm was noted, the temperature rising to approximately 35° C. After stirring for 6 hours at ambient temperature, monitoring by tlc (4:1 chloroform:ethyl acetate) indicated considerable starting material remained. Additional chloromethyl pivalate (8.4 g., 65 mmoles) was added and stirring at ambient temperature continued for 16 hours. Isolation as detailed in Preparation 1 gave pivaloyloxymethyl 3-methyl-7-(5-methyl-3-phenylisoxazole-4-carboxamido)ceph-3-em-4-carboxylate [25.3 g., 76%; Rf 0.8 (4:1 chloroform:ethyl acetate; ir (CH2Cl2) 1780, 1750, 1670 cm-1 ].

Provenance & Evidence