反应详情

The alcohol obtained in Step 1 (20.0 mmol) was dissolved in CH2Cl2 (100 mL). Dess-Martin periodinane (8.70 g, 20.5 mmol, 1 equiv.) was added, and the resulting solution stirred at room temperature for 18 h. The reaction mixture was then diluted with sat. aq. NaHCO3 (50 mL) and sat. aq. NaS2O3 (50 mL). The layers were separated, and the aqueous layer extracted with CH2Cl2 (2×100 mL. The combined organic layers were washed with sat. aq. NaHCO3 (100 mL) and brine (2×100 mL), dried (MgSO4), filtered, and concentrated under reduced pressure. The residue was purified by flash column chromatography (silica gel, EtOAc:pet ether=1:2 to 2:3) to give the resulting aldehyde (2.85 g, 14.8 mmol, 75% yield from the alcohol) as a colorless oil. 1H NMR (500 MHz, CDCl3) δ=9.76 (t, J=1.7 Hz, 1H), 7.37-7.26 (m, 5H), 4.50 (s, 2H), 3.49 (t, J=6.2 Hz, 2H), 2.46 (td, J=7.2, 1.8 Hz, 2H), 1.79-1.71 (m, 2H), 1.70-1.61 (m, 2H) ppm; 13C NMR (125 MHz, CDCl3) δ=202.6, 138.7, 128.6, 127.84, 127.79, 73.2, 70.0, 43.8, 29.4, 19.2 ppm; LRMS (ESI+ve): 215 (M+Na+).

1. customThe layers were separated
2. extractionthe aqueous layer extracted with CH2Cl2 (2×100 mL
3. washThe combined organic layers were washed with sat. aq. NaHCO3 (100 mL) and brine (2×100 mL)
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by flash column chromatography (silica gel, EtOAc:pet ether=1:2 to 2:3)