1%; 3%; 42%; 5%; 2%; 2.5%; 10%; 20% |
With aluminum (III) chloride; iron(III) chloride; sodium chloride; In melt; at 150 - 185℃; for 0.166667h; |
General procedure: A mixture of substrate 7 (1.38 g, 8.0 mmol) and anhydride 9 (2.67 g, 16.0 mmol) was added to the melt of anhydrous AlCl3 (8.54 g, 64.0 mmol), NaCl (1.87 g, 32.0 mmol) and anhydrous FeCl3 (1.30 g, 8.0 mmol) with vigorous stirring at 150 C, the temperature of the mixture was increased to 180-185 C and maintained for 10 min. Then, the reaction mixture was cooled to room temperature, treated with 10% aqueous HCl (60 mL), and allowed to stand for 12 h. The product formed was separated, washed with hot (55-60 C) water (10×40 mL), dried to the constant weight, and subjected to chromatography on a column with SiO2. The elution with the mixture of hexane-benzene (10 : 1) gave compound 2 (0.066 g, 2.5%), the elution with the mixture of hexane-benzene (4 : 1) gave compound 1 (0.99 g, 42%), the elution with benzene gave compound 10 (0.045 g, 2%) identical to the sample described above. The combined acidic mother liquor and washing water (460 mL) were extracted with AcOEt (6×50 mL), the combined extracts were washed with saturated aqueous NaCl (3×50 mL), and dried with Na2SO4. The solvent was evaporated at reduced pressure, the residue was subjected to chromatography on a column with SiO2. The elution with the mixture of hexane-acetone (9 : 1) gave compound 14 (0.057 g, 5%), the elution with the mixture of hexane-acetone (8 : 1) gave compound 15 (0.034 g, 3%), the elution with the mixture of hexane-acetone (7 : 1) gave compound 16 (0.011 g, 1%), the elution with the mixture of hexane-acetone (5 : 1) gave compound 12 (0.232 g, 20%), and the elution with the mixture of hexane-acetone (4 : 1) gave compound 13 (0.07 g, 10%) identical to the sample described above. |