反应详情

To 1-(2-hydroxyethyl)-piperazine (3.36 g, 25.8 mmol) in dichloromethane (25 mL) was added tert-butyldimethylsilylchloride (3.89 g, 25.8 mmol). The reaction mixture was stirred at room temperature. The reaction mixture was stirred overnight, then diluted 1× with CH2Cl2 and extracted against 0.5 N NaOH (100 mL). The aqueous was extracted further with 10% methanol in CH2Cl2 (3×100 mL). The combined organics were dried with Na2SO4 and concentrated in vacuo. Silica gel chromatography (gradient elution 0 to 100% B (7% methanol in DCM+1% NH4OH additive) against A (3% methanol in DCM+0.175% NH4OH additive) afforded compound 246 (4.71 g, 74.7% yield). 1H NMR (500 MHz, CDCl3) δ 0.06 (s, 6 H) 0.90 (s, 9 H) 2.36-2.59 (m, 6 H) 2.89 (t, J=4.77 Hz, 4 H) 3.76 (t, J=6.48 Hz, 2 H) ppm.

1. stirringThe reaction mixture was stirred overnight
2. extractionextracted against 0.5 N NaOH (100 mL)
3. extractionThe aqueous was extracted further with 10% methanol in CH2Cl2 (3×100 mL)
4. dry with materialThe combined organics were dried with Na2SO4
5. concentrationconcentrated in vacuo
6. washSilica gel chromatography (gradient elution 0 to 100% B (7% methanol in DCM+1% NH4OH additive) against A (3% methanol in DCM+0.175% NH4OH additive)