反应详情

To a solution of ethyl 2-isothiocyanato-4,5-dimethylthiophene-3-carboxylate (Example 50b) (1.21 g, 5.27 mmol) in dichloromethane (10 mL) was added ammonia (7 M in MeOH, 1.12 mL, 7.91 mmol) at 0° C. The reaction mixture was then stirred at room temperature for 3 h, quenched with water and extracted with dichloromethane (3×). The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated. The dark orange residue was purified by chromatography on silica gel (Gradient 0-50% EtOAc in Hexanes) to give the title compound (37.1 mg, 3%). 1H NMR (400 MHz, DMSO-d6) δ 1.32 (t, 3H, J=7.1 Hz), 2.18 (s, 3H), 2.19 (s, 3H), 4.30 (q, 2H, J=7.1 Hz), 8.43 (s, 2H), 11.38 (s, 1H). MS 259 (MH+).

1. customquenched with water
2. extractionextracted with dichloromethane (3×)
3. washThe combined organic layers were washed with brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe dark orange residue was purified by chromatography on silica gel (Gradient 0-50% EtOAc in Hexanes)