[OH:1][C:2]1[CH:3]=[C:4]([CH:7]=[CH:8][C:9]=1O)[CH:5]=[O:6].[C:11](=[O:14])([O-])[O-].[K+].[K+].[CH2:17](I)[CH2:18][CH:19]([CH3:21])[CH3:20].Cl>CN(C)C=O.O.C(OCC)(=O)C>[CH2:17]([O:1][C:2]1[CH:3]=[C:4]([CH:7]=[CH:8][C:9]=1[O:14][CH2:11][CH2:3][CH:4]([CH3:7])[CH3:5])[CH:5]=[O:6])[CH2:18][CH:19]([CH3:21])[CH3:20]
In 50 ml of N,N-dimethylformamide are suspended 5.0 g of 3,4-dihydroxybenzaldehyde, 15.5 g of potassium carbonate and 14 ml of isopentyl iodide. The mixture is stirred at 60° C. for 2 hours. The reaction mixture is added to a mixture of ethyl acetate and water, pH is adjusted to 2 with 6 mol/L hydrochloric acid, and the organic layer is separated. The organic layer is washed with water and saturated aqueous solution of sodium chloride successively and dried over anhydrous magnesium sulfate, and then the solvent is distilled off under reduced pressure. The residue thus obtained is purified by silica gel column chromatography (eluent; hexane:ethyl acetate=10:1) to obtain 9.4 g of 3,4-diisopentyloxybenzaldehyde as a light yellow oily product.
Loading…
