反应详情

温度

-10 °C

6 ml (40 mmol) of 1,2,4-trimethoxybenzene are introduced into 80 ml of dry CH2Cl2 and the mixture is cooled to −10° C. with stirring. 6-Bromohexanoyl chloride (6.2 ml, 40 mmol) dissolved in 20 ml of CH2Cl2 is then added dropwise. AlCl3 (5.6 g, 42 mmol) is progressively introduced in small portions into the reaction mixture. The reaction is maintained with stirring for 8 h with a return to ambient temperature. The reaction mixture is then poured onto ice (200 ml) and acidified to pH 1 using HCl. The mixture is stirred until it returns to ambient temperature, 1 h. After evaporation of the CH2Cl2, the mixture is extracted with AcOEt, and the organic phases are separated, dried over MgSO4, filtered and evaporated. The residue is subjected to flash chromatography over SiO2 with a gradient of pure heptane to heptane-AcOEt 50-50. The pure fractions are evaporated to obtain 13.6 g (yield=99%) of crystals. TLC SiO2 (heptane-ACOEt 70-30) Rf=0.5; 1H NMR (CDCl3): 7.41 (s, 1H), 6.50 (s, 1H), 3.95 (s, 3H), 3.91 (s, 3H), 3.87 (s, 3H), 3.43 (t, 2H, J=6.76 Hz), 2.98 (t, 2H, J=6.32 Hz), 1.91 (m, 2H), 1.71 (m, 2H), 1.51 (m, 2H).

1. additionis then added dropwise
2. temperatureThe reaction is maintained
3. stirringwith stirring for 8 h with a return to ambient temperature
4. additionThe reaction mixture is then poured onto ice (200 ml)
5. stirringThe mixture is stirred until it
6. customAfter evaporation of the CH2Cl2
7. extractionthe mixture is extracted with AcOEt
8. customthe organic phases are separated
9. dry with materialdried over MgSO4
10. filtrationfiltered
11. customevaporated
12. customThe pure fractions are evaporated