Methyl chloroformate → p-Nitrobenzyl alpha-[3-phenoxymethyl-7-oxo-4-thia-2,6-diazabicyclo[3,2,0]hept-2-en-6-yl]-alpha-(1-methoxycarbonyloxyethylidene)acetate

Participants

Reaction Steps

To a stirred solution of p-nitrobenzyl α-[3-phenoxymethyl-7-oxo-4-thia-2,6-diazabicyclo[3,2,0]hept-2-en-6-yl]-α-(1-hydroxyethylidene)acetate (500 mg) in tetrahydrofuran (20 ml) are added dropwise methyl chloroformate (200 mg) and triethylamine (216 mg) under ice cooling. After 1 hour, the reaction mixture is poured into ice water, and is extracted with ethyl acetate. The extract solution is washed with water, dried, and evaporated to give p-nitrobenzyl α-[3-penoxymethyl-7-oxo-4-thia-2,6-diazabicyclo[3,2,0]hept-2-en-6-yl]-α-(1-methoxycarbonyloxyethylidene)acetate (546 mg). Foam. Yield: 97%.

Provenance & Evidence