反应详情

温度

-78 °C

A solution of 8 (441 mg, 1.93 mmol) in anhydrous THF (1.55 mL) was added dropwise to a solution of nBuLi (2.5 M in hexanes, 1.16 mL, 2.90 mmol) in anhydrous THF (1.26 mL) at room temperature. After one hour, the solution was cooled to −78° C. and methyl iodide (480 μL, 7.73 mmol) was added. The resulting solution was warmed to room temperature over 12 hours, and the reaction was quenched by the addition of saturated aqueous NH4Cl. Water (5 mL) was added and the solution was extracted with CH2Cl2 (3×10 mL). Combined organic fractions were dried (Na2SO4), filtered, and concentrated. The residue was purified via column chromatography (SiO2, 6:1→4:1; Hexane:EtOAc) to afford 9 as a yellow oil (314 mg, 67%): 1H NMR (CDCl3, 500 MHz) 6.38 (d, J=2.2 Hz, 1H), 6.24 (d, J=2.1 Hz, 1H), 5.08 (d, J=3.6 Hz, 2H), 5.06 (d, J=2.6 Hz, 2H), 3.72 (s, 3H), 3.40 (s, 6H), 1.97 (s, 3H); 13C NMR (CDCl3, 125 MHz) 160.3, 157.8, 155.4, 108.2, 93.9, 93.8, 93.7, 92.9, 55.0, 55.0, 54.6, 7.0; IR (film) νmax 2953, 2934, 2905, 1597, 1497, 1396, 1215, 1144, 1126, 1074, 1059, 1028, 922, 822 cm−1; HRMS (ESI+) m/z: [M+H]+ calcd for C12H18O5, 243.1233; found, 243.1223.

1. temperatureThe resulting solution was warmed to room temperature over 12 hours
2. customthe reaction was quenched by the addition of saturated aqueous NH4Cl
3. additionWater (5 mL) was added
4. extractionthe solution was extracted with CH2Cl2 (3×10 mL)
5. dry with materialCombined organic fractions were dried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was purified via column chromatography (SiO2, 6:1→4:1; Hexane:EtOAc)