反应详情

To a solution of (R)-1-[4-(4-quinoxalin-2-yl-piperazin-1-yl)-pyrimidin-2-yl]-ethyl acetate (prepared according to the method of Example 1, Step A, 14.1 g, 37.2 mmol) in a 3:1:1 mixture of tetrahydrofuran/water/methanol (375 mL) was added lithium hydroxide hydrate (4.7 g, 112 mmol). This mixture was stirred at room temperature for 1 h 45 min, concentrated, and extracted with chloroform (6×). The combined organic extracts were dried over sodium sulfate, filtered, evaporated, and purified by flash column chromatography (2×; 2% methanol/chloroform) to give 11.3 g (90%) of the title compound as a pale yellow solid after tritration with hexanes. mp: 106.5-108° C.; 1H NMR (CDCl3, 250 MHz) δ8.62 (s, 1H), 8.26 (d, 1H), 7.92 (dd, 1H), 7.72 (dd, 1H), 7.61 (td, 1H), 7.44 (td, 1H), 6.45 (d, 1H), 4.75 (m, 1H), 3.95-3.85 (c, 8H), 1.54 (d, 3H); MS (CI/NH3) 337 (MH+); [α]D +15.3 (c 2.3, MeOH).

1. concentrationconcentrated
2. extractionextracted with chloroform (6×)
3. dry with materialThe combined organic extracts were dried over sodium sulfate
4. filtrationfiltered
5. customevaporated
6. custompurified by flash column chromatography (2×; 2% methanol/chloroform)