Lithium hydroxide, monohydrate → (7-Methoxymethoxymethyl-1,1-dioxo-1,4-dihydro-1lambda6-thieno[2,3-e][1,2,4]thiadiazin-3-yl)-acetic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of (7-methoxymethoxymethyl-1,1-dioxo-1,4-dihydro-1λ6-thieno[2,3-e][1,2,4]thiadiazin-3-yl)-acetic acid ethyl ester (0.54 g, 1.55 mmol) in tetrahydrofuran (5 mL) and water (5 mL) was added lithium hydroxide monohydrate (0.33 g, 7.75 mmol). The reaction was stirred at 25° C. for 1 h before it was cooled to 0° C. The reaction was quenched via the addition of 6.0 M aqueous hydrochloric acid solution until a pH of 1-2 was reached. The resulting mixture was extracted with ethyl acetate (3×10 mL). The organic layers were combined, dried over magnesium sulfate, filtered and concentrated in vacuo to afford the crude product, (7-methoxymethoxymethyl-1,1-dioxo-1,4-dihydro-1λ6-thieno[2,3-e][1,2,4]thiadiazin-3-yl)-acetic acid (0.39 g, 1.21 mmol, 78%), which was used in the next step without further purification.

Provenance & Evidence