Hydrochloric Acid → Ethyl 9-(2,3-Dichlorophenyl)-1,1-dioxo-2,3,4,5,6,9-hexahydro-7-methylpyrido-[2,3-f][1,4]thiazepine-8-carboxylate

Participants

Reaction Steps

A mixture of ethyl 9-(2,3-dichlorophenyl)-4-(t-butyloxycarbonyl)-1,1-dioxo-2,3,4,5,6,9-hexahydro-7-methylpyrido[2,3-f][1,4]thiazepine-8-carboxylate (2.45 g, 4.6 mmole) from Example 7, in ethyl acetate (150 mL) was cooled to 0° C. and saturated with gaseous hydrogen chloride. The mixture was warmed to room temperature. The reaction was then again chilled to 0° C. and shaken with 200 mL of cold 4 N NaOH. The aqueous layer was separated and extracted with 2×100 mL of chloroform. The ethyl acetate layer was dried with brine and the combined organic extracts were dried over Na2SO4. The solvents were evaporated under reduced pressure and the residue triturated with ether to give the product (1.86 g, 94% yield).

Provenance & Evidence