반응 #430486

반응 방정식

chlorosulfonyl isocyanate

formic acid

17β-tert-butyldimethylsilyloxy-3-hydroxyestra-1,3,5(10)-triene-2-carbox aldehyde

17β-tert-butyldimethylsilyloxy-3-hydroxyestra-1,3,5(10)-triene-2-carboxaldehyde

sodium hydride

→

2a

수율 18.3%

3,17β-dihydroxyestra-1,3,5(10)-triene-2-carboxaldehyde

수율 18.3%

용매

CH2Cl2

CH2Cl2

DMF

반응 조건

후처리

1. 1
   workup.STIRRINGThe reaction mixture was stirred for 1 h
2. 2
   workup.ADDITIONthe pre-prepared reagent was added
3. 3
   workup.STIRRINGstirring
4. 4
   workup.WAITcontinued for 4 h at room temperature
5. 5
   기타The reaction mixture was quenched with saturated aqueous NH4Cl at 0° C.
6. 6
   추출extracted with EtOAc
7. 7
   세척The combined organic layers were washed with H2O
8. 8
   건조with saturated aqueous NaCl, and dried (MgSO4)
9. 9
   여과The desiccant was filtered
10. 10
    기타the solvent was evaporated at reduced pressure
11. 11
    기타The residue was purified by column chromatography (silica gel)

실험 절차

To a solution of chlorosulfonyl isocyanate (0.13 mL, 1.5 mmol) in CH2Cl2 (1.0 mL) was added formic acid (0.31 mL of a CH2Cl2 solution, 5.0M, 1.6 mmol) at 0° C. The reaction mixture was warmed to room temperature and stirred for 1 h. To a solution of 17β-tert-butyldimethylsilyloxy-3-hydroxyestra-1,3,5(10)-triene-2-carbox aldehyde (9, 0.129 g, 0.31 mmol) in DMF (3.0 mL) was added sodium hydride (0.044 g of a mineral oil dispersion, 60%, 1.1 mmol) at 0° C. The reaction mixture was stirred for 1 h, the pre-prepared reagent was added, and stirring continued for 4 h at room temperature. The reaction mixture was quenched with saturated aqueous NH4Cl at 0° C. and extracted with EtOAc. The combined organic layers were washed with H2O, then with saturated aqueous NaCl, and dried (MgSO4). The desiccant was filtered and the solvent was evaporated at reduced pressure. The residue was purified by column chromatography (silica gel) using n-hexane:acetone (2:1→1:1, v/v) to afford 0.017 g of 2a (18% yield) and 0.030 g of 10 (27% yield), m.p. 170°-172° C.

출처