反应详情

To crude tert-butyl 7-((3-chlorobenzyl)oxy)-3-(2-ethoxy-2-oxoethyl)-2-oxo-3,4-dihydroquinoline-1(2H)-carboxylate (115.7 g, 244.1 mmol) was added a 4.0 M 1,4-dioxane hydrochloride solution (200 mL, 0.8 mol) in an ice bath. After addition, the ice bath was removed and the reaction was warmed to ambient temperature. The reaction was concentrated to a yellow oil and azeotroped with toluene (2×250 mL) to furnish a brown oil. The oil was diluted in toluene (400 mL) followed by 2-propanol (400 mL). The resulting white ppt that was formed was filtered and washed with 2-propanol to furnish the desired product as a white solid. The mother liquor was concentrated to a brown solid that was triturated with 2-propanol (400 mL), filtered and washed with 2-propanol to furnish a second crop of product (38.3 g). The two crops were combined to give (50.3 g, 55%) of the title compound. 1H NMR (400 MHz, CDCl3) δ 7.88 (s, 1H), 7.43 (s, 1H), 7.35-7.29 (m, 3H), 7.06 (d, J=8.3 Hz, 1H), 6.59 (dd, J=8.3, 2.4 Hz, 1H), 6.39 (d, J=2.4 Hz, 1H), 5.02 (s, 2H), 4.23-4.15 (m, 2H), 3.12-2.92 (m, 3H), 2.92-2.77 (m, 1H), 2.48 (dd, J=16.2, 7.5 Hz, 1H), 1.29 (t, J=7.1 Hz, 3H). [M+H]=374.2.

1. additionAfter addition
2. customthe ice bath was removed
3. concentrationThe reaction was concentrated to a yellow oil
4. customazeotroped with toluene (2×250 mL)
5. customto furnish a brown oil
6. customThe resulting white ppt that was formed
7. filtrationwas filtered
8. washwashed with 2-propanol