反应详情

A solution of 5-chloro-4-nitrothiophene-2-carboxylic acid methyl ester (6.03 g, 27.2 mmol), glycine ethyl ester hydrochloride (4.18 g, 29.9 mmol) and potassium carbonate (9.4 g, 68 mmol) in acetonitrile (200 mL) was stirred 4 h at 70° C. Quenched in ice/water. The resulting precipitation was collected by filtration, washed with water and dried to give methyl 5-(2-ethoxy-2-oxoethylamino)-4-nitrothiophene-2-carboxylate 19 (7.02 g, 89%). NMR (400 MHz, CDCl3) 1.35 (t, J=7.0 Hz, 3H), 3.87 (s, 3H), 4.11 (d, J=5.5 Hz, 2H), 4.33 (q, J=14.0 and 7.0 Hz, 2H), 8.04 (s, 1H), 8.75 (br s, 1H). (m/z)=289 (M+H)+.

1. customQuenched in ice/water
2. customThe resulting precipitation
3. filtrationwas collected by filtration
4. washwashed with water
5. customdried