Sodium hydride → HCID 20492743, compound

Participants

Reaction Steps

To a suspension of sodium hydride (5.13 g, 60% oil dispersion, washed with dry petroleum ether) in dimethylformamide (110 ml) was added 7-chloro-4-methyl-2H-1,4-benzothiazin-3(4H)one 1,1-dioxide (30 g) at 5° to 10° C. The mixture was allowed to warm to room temperature and stirred for 15 minutes for the preparation of the sodium salt. The reaction mixture was then cooled in an ice bath and a solution of ethyl cyanoformate (16.29 g) in dimethylformamide (15 ml) was added dropwise over 30 minutes. After being stirred for one hour, the mixture was quenched with acetic acid (14 ml), poured into ice water, and extracted with ethyl acetate. The organic layer was washed with water, dried over magnesium sulfate, and evaporated under reduced pressure. The oily residue was crystallized from ethanol to afford 31 g of 7-chloro-2-ethoxycarbonyl-4-methyl-2H-1,4-benzothiazin-3(4H)one 1,1-dioxide, mp 86° to 91° C. (melt).

Provenance & Evidence