反应详情

(13b1 R1=pivaloyloxymethyl) To a stirred suspension of 12b1 (1.0 g, 1.97 mmol) in 10 mL of water, NaOH (158 mg, 3.94 mmol) in 2 mL of water was added. The mixture became clear (pH-9). A 5 mL aqueous solution of AgNO3 (807 mg, 4.75 mmol), was added. After 3 h of stirring at room temperature, the gray precipitate was collected by filtration, dried over P2O5, and pulverized in a mortar and pestle. The powder was suspended in dry toluene (15 mL) and pivaloyloxymethyl iodide (1.4 g, 5.7 mmol) was added and the mixture was stirred for 48 h at room temperature. After filtration the solvent was removed in vacuo and the crude product was purified by silica gel column chromatography eluting with 30% EtOAc-hexanes to give colorless sticky liquid (1.0 g, 69%). 1H NMR (CDCl3, 500 MHz) δ 1.22 (s, 18H), 2.64 (s, 3H), 5.73-5.8 (m, 4H), 6.43 (s, 1H), 7.31 (d, J=8.0 Hz, 2H), 7.58 (d, J=8.0 Hz, 2H). 13C NMR (CDCl3, 125 MHz) δ 18.5, 26.8, 38.7, 83.1, 113.8, 120.4, 127.9, 128.2, 131.3, 132.0, 138.6, 144.3, 151.3, 160.4, 161.9, 176.6. HRMS (M+H) calc, 733.0097; found, 733.0122

1. additionwas added
2. filtrationthe gray precipitate was collected by filtration
3. dry with materialdried over P2O5
4. stirringthe mixture was stirred for 48 h at room temperature
5. filtrationAfter filtration the solvent
6. customwas removed in vacuo
7. customthe crude product was purified by silica gel column chromatography
8. washeluting with 30% EtOAc-hexanes