反应详情

温度

50 °C

A 1-L pressure reactor was charged with 1-dimethylamino-2-(4-methylsulphonyl-2-nitrophenyl)ethene (54.0 g, 0.2 mol), 5.0% palladium on carbon hydrogenation catalyst (0.3 g) and tetrahydrofuran (500 mL). The reactor then was sealed, pressurized to approximately 30 bars absolute with hydrogen and heated with stirring to 50° C., at which point an exotherm caused the temperature to rise to approximately 85° C. The reaction mixture then was stirred at 60°-70° C. for 1 hour, after which time the reactor was cooled and vented. The reaction mixture was filtered to remove the catalyst and the filtrate was concentrated under reduced pressure to give a brown solid which was dissolved in ethyl acetate (500 mL) and washed with 1M aqueous hydrochloric acid (3×200 mL) and then water (2×200 mL). The organic layer was dried over magnesium sulfate and concentrated under reduced pressure to give a pale brown solid which was slurried in 53% weight:weight ethyl acetate in hexane (about 60 mL). The solid was collected by suction filtration and dried to give crude 1-hydroxy-6-methylsulphonylindole as a pale brown solid (33.1 g, 78% of theory). This crude product was recrystallized from acetonitrile to give a white crystalline product (17.8 g, 42% of theory). The filtrate from the recrystallization was concentrated in vacuo to a heavy slush which was cooled, filtered and washed with ice-cold acetonitrile to give a second crop of 1-hydroxy-6-methylsulphonylindole (10.7 g, 25% of theory) which was recrystallized twice from acetonitrile to give the product as a white, crystalline solid (3.8 g, 9% of theory). Thus, the total yield of 1-hydroxy-6-methylsulphonylindole was 21.6 g (51% of theory). Melting point 174°-176° C.; Rf (66% weight:weight ethyl acetate in hexane) 0.36. Calculated: C, 51.17; H, 4,29; N, 6.63. Found: C, 51.10; H, 4,16; N, 6.67.

1. customThe reactor then was sealed
2. temperatureheated
3. customto rise to approximately 85° C
4. stirringThe reaction mixture then was stirred at 60°-70° C. for 1 hour
5. temperatureafter which time the reactor was cooled
6. filtrationThe reaction mixture was filtered
7. customto remove the catalyst
8. concentrationthe filtrate was concentrated under reduced pressure
9. customto give a brown solid which
10. washwashed with 1M aqueous hydrochloric acid (3×200 mL)
11. dry with materialThe organic layer was dried over magnesium sulfate
12. concentrationconcentrated under reduced pressure
13. customto give a pale brown solid which
14. filtrationThe solid was collected by suction filtration
15. customdried
16. customto give crude 1-hydroxy-6-methylsulphonylindole as a pale brown solid (33.1 g, 78% of theory)
17. customThis crude product was recrystallized from acetonitrile
18. customto give a white crystalline product (17.8 g, 42% of theory)
19. customThe filtrate from the recrystallization
20. concentrationwas concentrated in vacuo to a heavy slush which
21. temperaturewas cooled
22. filtrationfiltered
23. washwashed with ice-cold acetonitrile