反应详情

To the solution (60 ml) in ethanol of 2.04 g of 2-(2-(ethoxycarbonyl)ethyl)-7-nitro-1,2,3,4-tetrahydroisoquinoline obtained in Example 2 was added 3.75 ml of 2N aqueous solution of sodium hydroxide, and the solution was stirred at room temperature for 14 hours. The solution was concentrated under reduced pressure, and to the residue were added 300 ml of isopropylalcohol and 0.60 ml of sulfuric acid. The solution was heated under reflux for 20 hours, and concentrated under reduced pressure. After adding saturated aqueous solution of sodium bicarbonate to the residue, the solution was extracted with ethyl acetate, washed with water, dried with anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain 1.58 g of 2-(2-(isopropyloxycarbonyl)ethyl)-7-nitro-1,2,3,4-tetrahydroisoquinoline (yield: 74%).

1. concentrationThe solution was concentrated under reduced pressure
2. additionto the residue were added 300 ml of isopropylalcohol and 0.60 ml of sulfuric acid
3. temperatureThe solution was heated
4. temperatureunder reflux for 20 hours
5. concentrationconcentrated under reduced pressure
6. additionAfter adding saturated aqueous solution of sodium bicarbonate to the residue
7. extractionthe solution was extracted with ethyl acetate
8. washwashed with water
9. dry with materialdried with anhydrous sodium sulfate
10. concentrationconcentrated under reduced pressure
11. customThe residue was purified by silica gel column chromatography