反应详情

Ethyl 5-(4-nitrophenyl)thiazole-2-carboxylate (Intermediate 2, step A, 3.6 g) was dissolved in THF (90 ml). 1 Molar aqueous NaOH (52 ml) was added and stirred at RT for 15-20 minutes. The reaction mixture was acidified with 1M HCl, extracted with EtOAc. The organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure to get pale yellow colored solid. Solid was crystallized in EtOAc/Pet ether to yield 2.48 g (76%) of the title compound. 1H NMR (DMSO-d6, 300 MHz): δ 14.21 (bs, 1H), 8.7 (s, 1H), 8.31 (d, 2H), 8.1 (d, 2H); MS (ES+): m/z 251 (M+1).

1. extractionextracted with EtOAc
2. washThe organic layer was washed with brine
3. dry with materialdried over Na2SO4
4. concentrationconcentrated under reduced pressure
5. customto get pale yellow colored solid
6. customSolid was crystallized in EtOAc/Pet ether