Methyl iodide → 6-chloro-7-methylsulfanyl-3-trifluoromethyl-1H-quinoxalin-2-one

Participants

Reaction Steps

A mixture of 6-chloro-7-fluoro-3-trifluoromethyl-quinoxalin-2-ol and 7-chloro-6-fluoro-3-trifluoromethyl-quinoxalin-2-ol (4.1 g, prepared similarly as described above from 4-chloro-5fluoro-1,2-diaminobenzene and ethyl trifluoropyruvate) was dissolved in DMF (140 ml) and sodium hydrogen sulfide monohydrate (3.5 g, 47 mmol) was added. The reaction mixture was stirred at room temperature for 1 hour and then iodomethane (3.5 ml) was added. Stirring was continued for 10 minutes and the reaction mixture was poured on ice/water (500 ml). The separated crystals were filtered, dried and recrystallised from ethanol to afford 1.73 g (38%) of 6-chloro-7-methylsulfanyl-3-trifluoromethyl-1H-quinoxalin-2-one.

Provenance & Evidence