反应详情

A solution of Ethyl 2-(2-(4-nitrophenyl)-2-oxoethylamino)-2-oxoacetate (step C product, 8.5 g) in POCl3 (55 ml) was refluxed for 6 hours. The reaction mixture was cooled, quenched with ice and neutralized with sodium carbonate. DCM was added to it and the organic and aqueous layers were separated. Organic layer was dried over Na2SO4, filtered and concentrated under reduced pressure to get dark brown residue. The residue was chromatographed on silica gel in 2:8 Ethyl acetate:Pet ether to get pale brown colored solid which was crystallized in chloroform/pet ether to yield 4.82 g (60%) of the title compound. 1HNMR (CDCl3, 300 MHz): δ 8.41 (d, 2H), 7.97 (d, 2H), 7.37 (s, 1H), 4.55 (q, 2H), 1.49 (t, 3H).

1. temperatureThe reaction mixture was cooled
2. customquenched with ice and neutralized with sodium carbonate
3. additionDCM was added to it
4. customthe organic and aqueous layers were separated
5. dry with materialOrganic layer was dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customto get dark brown residue
9. customThe residue was chromatographed on silica gel in 2:8 Ethyl acetate
10. customPet ether to get pale brown colored solid which
11. customwas crystallized in chloroform/pet ether