反应详情

温度

0 °C

N,N-Diisopropylethylamine (25.3 mL, 145 mmol) was slowly added to 2,4-dihydroxybenzaldehyde (5.00 g, 36.2 mmol) in anhydrous N,N-dimethylformamide (100 mL) over 5 minutes at room temperature. After 30 minutes, the solution was cooled to 0° C. and chloromethyl ethyl ether (14.2 mL, 145 mmol) was added and the mixture warmed to room temperature over 12 hours. The reaction was quenched by the addition of saturated aqueous NH4Cl solution and extracted with EtOAc (3×50 mL). The combined organic fractions were washed with saturated aqueous NaCl, dried (Na2SO4), filtered, and concentrated. The residue was purified via column chromatography (SiO2, 5:1→1:1 Hexane:EtOAc) to give 2a as a brown amorphous solid (9.10 g, 99%): 1H NMR (CDCl3, 400 MHz) δ 10.34 (d, J=2.4 Hz, 1H), 7.81 (dd, J=8.7, 2.8 Hz, 1H), 6.89 (t, J=2.5 Hz, 1H), 6.74 (m, 1H), 5.34 (d, J=2.8, 2H), 5.28 (d, J=2.8, 2H), 3.81-3.71 (m, 4H), 1.28-1.22 (m, 6H).

1. temperaturethe mixture warmed to room temperature over 12 hours
2. customThe reaction was quenched by the addition of saturated aqueous NH4Cl solution
3. extractionextracted with EtOAc (3×50 mL)
4. washThe combined organic fractions were washed with saturated aqueous NaCl
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was purified via column chromatography (SiO2, 5:1→1:1 Hexane:EtOAc)