[CH3:1][C:2]1([CH3:13])[CH2:6][C:5]2[C:7]([CH3:12])=[CH:8][CH:9]=[C:10]([CH3:11])[C:4]=2[O:3]1.[CH3:14][O:15]C(Cl)Cl>ClCCl>[CH3:1][C:2]1([CH3:13])[CH2:6][C:5]2[C:7]([CH3:12])=[C:8]([CH:14]=[O:15])[CH:9]=[C:10]([CH3:11])[C:4]=2[O:3]1To a solution of 110 g of the 2,3-dihydro-2,2,4,7-tetramethylbenzofuran in 500 ml of absolute dichloromethane was added 68.5 ml of titanium chloride(IV) and 56.5 ml of α,α-dichloromethyl methyl ether at 0° C. With stirring at room temperature for 45 minutes and refluxing for 15 minutes, the reaction mixture was quenched with 1 l of water and the aqueous layer was extracted with dichloromethane. The combined organic extracts were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to afford a crude product. Final purification was carried by recrystallization to afford 104 g of 2,3-dihydro -2,2,4,7-tetramethyl-benzofuran-5-carboxaldehyde as a white solid.
불러오는 중…