反应详情

To a suspension of LiAlH4 (437 mg, 11.5 mmol) in dry tetrahydrofuran (30 mL) under nitrogen atmosphere, a solution of 5-chloro-2-hydroxybenzamide 74 (1.5 g, 5.7 mmol) in THF (10 mL) was added and the mixture was refluxed for 3 h. After cooling, the excess of LiAlH4 was destroyed with a saturated solution of sodium sulfate. The mixture was filtered on MgSO4 and the filtrate concentrated in vacuo. The residue was partitioned between water (30 mL) and CH2Cl2 (30 mL). The aqueous phase was separated and extracted with CH2Cl2 (20 mL×2). The combined organic phases were dried over Na2SO4, filtered and concentrated. The obtained solid was recrystallized from ethanol obtaining 787 mg of pure product (yield 88%). 1H NMR (CDCl3, 300 MHz) δ 7.10 (dd, J=6.6, 2.7 Hz, 1H), 6.94 (d, J=2.4 Hz, 1H), 6.76 (d, J=8.7 Hz, 1H), 4.10 (br s, 2H), 1.61 (br s, 2H). MS (m/e) (API-ES) 158 (M+H)+, m.p. 160-162° C.

1. temperaturethe mixture was refluxed for 3 h
2. temperatureAfter cooling
3. customthe excess of LiAlH4 was destroyed with a saturated solution of sodium sulfate
4. filtrationThe mixture was filtered on MgSO4
5. concentrationthe filtrate concentrated in vacuo
6. customThe residue was partitioned between water (30 mL) and CH2Cl2 (30 mL)
7. customThe aqueous phase was separated
8. extractionextracted with CH2Cl2 (20 mL×2)
9. dry with materialThe combined organic phases were dried over Na2SO4
10. filtrationfiltered
11. concentrationconcentrated