Ethyl iodoacetate → Ethyl 2-(2,4-dioxo-4H-thieno[3,2-d][1,3]oxazin-1-yl)acetate

Participants

Reaction Steps

Sodium hydride (851 mg, 60% dispersion in oil) in dry N,N-dimethylformamide (DMF) (15 ml) was cooled under argon in an ice bath. A solution of 1H-thieno[3,2-d][1,3]oxazine-2,4-dione (3 g) in DMF (10 ml) was added over ca 20 min. The reaction mixture was stirred for 30 min at room temperature, then recooled in an ice bath. Ethyl iodoacetate (4.55 g) was added and the mixture stirred at room temperature for ca 2 h. The solution was concentrated to about half volume and cooled in an ice bath. Water was added (ca 200 ml). After 10 min the precipitate was filtered off and washed with water and hexane and dried at 40° C. in vacuo overnight. The title compound was obtained as a white solid (3.62 g, 80%). 1H-NMR (CDCl3) δ 1.30 (3H, t), 4.28 (2H, q), 4.71 (2H, s), 6.77 (1H, d), 7.87 (1H, d). (APCI+) Found (M+1)=256, C10H9NO5S requires 255.

Provenance & Evidence