反应详情

温度

80 °C

A mixture of the product from step (iv) (51.7 g) and 5 M KOH (517 g) in ethanol (204 g) was heated at 80° C. for 4 hours. After the solvent was evaporated under reduced pressure, the residue was diluted with water (259 mL) and washed with t-butyl methyl ether (390 g) at 25° C. The solution was cooled to 5° C. and the pH of the solution was adjusted to pH 5 with conc. HCl. The resulting precipitate was collected by filtration, washed with a solution of water (200 mL) and MeCN (200 g) and dried to afford the subtitle compound as a solid, 57.0 g; containing 4.5% weight of water; 1H NMR DMSO-d6: 7.12 (d, 2H), 7.02 (d, 2H), 6.32 (t, 1H), 5.94 (brs, 2H), 3.71 (s, 2H), 3.46 (s, 2H), 3.27-3.23 (m, 2H), 2.00 (s, 3H), 1.48-1.41 (m, 2H), 1.27-1.21 (m, 2H), 1.18-1.13 (m, 2H), 0.82 (t, 3H).

1. customAfter the solvent was evaporated under reduced pressure
2. additionthe residue was diluted with water (259 mL)
3. washwashed with t-butyl methyl ether (390 g) at 25° C
4. temperatureThe solution was cooled to 5° C.
5. filtrationThe resulting precipitate was collected by filtration
6. washwashed with a solution of water (200 mL) and MeCN (200 g)
7. customdried