Potassium Carbonate → Ethyl 2-[(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl]-2H-thieno[3,2-e]-1,2-thiazine-3-carboxylate 1,1-dioxide

Participants

Reaction Conditions

Reaction Steps

The product from Step A (46.5 g, 0.292 mol) was added in portions to a solution (room temperature) of (N-[[3-formyl-thien-2-yl]sulfonyl]glycine ethyl ester (27 g, 0.97 mol) in dimethylsulfoxide (200 mL) which contained potassium carbonate (40.45 g, 0.292 mol). This mixture was stirred at 55° C. for 12 h, cooled to 0° C, diluted with water, and extracted with ethyl acetate (3×200 mL). The combined extracts were dried (MgSO4) and evaporated to a crude oil which was purified by column chromatography (silica, 30% ethyl acetate in hexane) to give 18 g (50%) of the desired product as an oil.

Provenance & Evidence