反应详情

温度

40 °C

2,3,5-Trimethylhydroquinone (50.2 g) in 400 mL EtOH was treated with a solution of 10 g Na2S2O3.5H2O in 50 mL H2O followed by Me2SO4 (68 mL, 2.2 equiv.). To this was added slowly 10 M NaOH (100 mL, 3.0 equiv.) via dropping funnel until the reaction temperature reached 60° C. (65 mL added). The remaining 35 mL NaOH solution was added slowly, dropwise over 1 h to maintain a minimum 40° C. reaction temperature. After 2.0 h, the reaction vessel had returned to ambient temperature and an additional portion of Me2SO4 (10 mL, 13.3 g,) was added causing a slight rise in temperature. After 1 h, the reaction had returned to room temperature, 100 mL conc. NH4OH was added and let stir overnight. The red-brown solution was diluted with isopropyl acetate, the organics washed with 200 mL H2O, 200 mL 1.0 M NaHCO3 and 2×200 mL saturated aqueous NaCl, dried over MgSO4 and concentrated to give 61.2 g of 1,4-dimethoxy-2,3,5-trimethylbenzene as a brown oil. 1H NMR (400 MHz, CDCl3) δ=6.53 (s, 1 H), 3.78 (s, 3 H), 3.66 (S, 3 H), 2.28 (s, 3 H), 2.20 (s, 3 H), 2.12 (s, 3 H) ppm.

1. customreached 60° C.
2. addition(65 mL added)
3. customreaction temperature
4. customhad returned to ambient temperature
5. waitAfter 1 h
6. customhad returned to room temperature
7. washthe organics washed with 200 mL H2O, 200 mL 1.0 M NaHCO3 and 2×200 mL saturated aqueous NaCl
8. dry with materialdried over MgSO4
9. concentrationconcentrated