反应详情

温度

5 °C

5.67 g (20 mmol) of N-(2-methoxy-3,4-methylenedioxybenzyl)-N-methylaminoacetaldehyde dimethylacetal (5) was dissolved in 40 ml of 6N sulfuric acid and the solution was stirred under heating at 76°-77° C. for 1.5 hour. The solution was cooled and added with 25% aqueous solution of sodium hydroxide at a temperature below 30° C. to make the pH of the solution about 11. The solution was extracted with 35 ml and then with 10 ml of methylene chloride successively, and the extracts were joined, washed with 20 ml of water and dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure and the residue was added with 12 ml of ethanol and dissolved by heating. Then, the solution was cooled to 5° C. to be crystallized. The crystals were filtered out, washed with 3 ml of cold ethanol and then dried under reduced pressure to obtain 3.71 g of 4-hydroxy-8-methoxy-2-methyl-6,7 -methylenedioxy-1,2,3,4-tetrahydroisoquinoline (6). Yield: 78%, melting point: 152°-153° C.

1. temperatureunder heating at 76°-77° C. for 1.5 hour
2. temperatureThe solution was cooled
3. extractionThe solution was extracted with 35 ml
4. washwashed with 20 ml of water
5. dry with materialdried over anhydrous magnesium sulfate
6. distillationThe solvent was distilled off under reduced pressure
7. additionthe residue was added with 12 ml of ethanol
8. dissolutiondissolved
9. temperatureby heating
10. customto be crystallized
11. filtrationThe crystals were filtered out
12. washwashed with 3 ml of cold ethanol
13. customdried under reduced pressure