反应详情

To a solution of 41 (3 g, 22.90 mmol), in a solvent mixture of CH2Cl2 (100 mL) and THF (50 mL) at room temperature were added Et3N (7.96 mL, 57.25 mmol), followed by benzenesulfonyl chloride (6.13 mL, 48.09 mmol). The mixture was stirred overnight at room temperature and then treated with a saturated aqueous solution of NH4Cl. The phases were separated and the aqueous layer was extracted several times with CH2Cl2. The combined organic extracts were dried over (MgSO4) and evaporated under reduced pressure giving a mixture of mono- and bis-alkylated products. The residue was dissolved in THF (50 mL) and water (50 mL), and LiOH was added. The resulting mixture was stirred for 4 h at room temperature, and then was treated with 1N HCl until pH 1. The phases were separated and the aqueous layer was extracted several times with AcOEt. The combined organic extracts were dried over (MgSO4) and then evaporated under reduced pressure, yielding compound 42 (2.95 g, 48%) as a white powder: 1H NMR (300 MHz, acetone-d6) δ 7.86 (d, J=7 Hz, 2H), 7.64-7.57 (m, 3H), 6.47 (br. s, 1H), 2.96-2.89 (m, 2H), 2.27-2.23 (m, 2H), 1.60-1.50 (m, 4H).

1. customThe phases were separated
2. extractionthe aqueous layer was extracted several times with CH2Cl2
3. dry with materialThe combined organic extracts were dried over (MgSO4)
4. customevaporated under reduced pressure
5. customgiving
6. additiona mixture of mono- and bis-alkylated products
7. stirringThe resulting mixture was stirred for 4 h at room temperature
8. customThe phases were separated
9. extractionthe aqueous layer was extracted several times with AcOEt
10. dry with materialThe combined organic extracts were dried over (MgSO4)
11. customevaporated under reduced pressure