反应详情

温度

-10 °C

N-chlorosuccinimide (3.85 g, 29.35 mmole) was suspended in dichloroethane (40 ml) under a nitrogen atmosphere and cooled to −10° C. using an ice-salt-acetone bath. Dimethylsulfide (3 ml) was slowly added with stirring over a period of about 5 minutes. The mixture was stirred at this temperature for 10 minutes beyond the addition, at which time the ice-salt-acetone bath was replaced by a dry-ice acetone bath and the temperature was lowered to −50° C. To this solution was added 2-methylindole (3.85 g, 29.35 mmole) dissolved in dichloroethane (40 ml) slowly with stirring. The reaction mixture was stirred while allowing the temperature to reach 20° C. over about an hour. Diethyl ether (90 ml) was added with stirring and the precipitate which formed was filtered, washed well with ether, and dried overnight in a vacuum oven at room temperature. The free-flowing powder of (2-methyl-1H-indol-3-yl)-dimethylsulfonium chloride thus obtained was used without further purification in the following step.

1. customwas replaced by a dry-ice acetone bath
2. customwas lowered to −50° C
3. stirringwith stirring
4. stirringThe reaction mixture was stirred
5. waitto reach 20° C. over about an hour
6. stirringwith stirring
7. customthe precipitate which formed
8. filtrationwas filtered
9. washwashed well with ether
10. customdried overnight in a vacuum oven at room temperature