反应详情

温度

80 °C

Ammonium chloride (1.04 g) and iron (777 mg) were added to a solution of Methyl 3-methyl-2-(5-(4-nitrophenyl)thiazole-2-carboxamido)butanoate (Intermediate 2, step C, 2.15 g) in EtOH (21.5 ml), THF (8.6 ml), and Water (8.6 ml). The reaction mixture was refluxed at 80° C. for 3 hours. It was then cooled, filtered through celite and the solvent was removed under reduced pressure to get dark brown residue. The residue was taken in water and extracted with ethyl acetate. The organic layer was separated, dried over Na2SO4 and concentrated to get dark brown residue which was purified by column on silica gel in 2.5:7.5 EtOAc:chloroform to get yellow sticky solid which was crystallized in DCM/pet ether to yield 1.82 g (91%) of the title compound. 1HNMR (DMSO-d6, 300 MHz): δ 8.59 (d, 1H), 8.15 (s, 1H), 7.42 (d, 2H), 6.63 (d, 2H), 5.76 (bs, 2H), 4.31 (m, 1H), 3.67 (s, 3H), 2.27 (m, 1H), 0.91 (d, 6H); MS (ES+): m/z 334 (M+1).

1. temperatureIt was then cooled
2. filtrationfiltered through celite
3. customthe solvent was removed under reduced pressure
4. customto get dark brown residue
5. extractionextracted with ethyl acetate
6. customThe organic layer was separated
7. dry with materialdried over Na2SO4
8. concentrationconcentrated
9. customto get dark brown residue which
10. customwas purified by column on silica gel in 2.5:7.5 EtOAc
11. customchloroform to get yellow sticky solid which
12. customwas crystallized in DCM/pet ether