Ethanesulfonylchloride, 2-chloro- → Tak-653

Participants

Reaction Steps

To a suspension of NaH (60%, 5.29 g) in THF (dry) (100 mL) was added 2-chloroethanesulfonyl chloride (5.57 ml) at 0° C. and the mixture was stirred for 10 min at the same temperature. A solution of 3-(4-(cyclohexyloxy)phenyl)-5-methylpyrazin-2-amine (7.5 g) in THF (dry) (75 mL) was added at 0° C. and the mixture was stirred at room temperature under nitrogen for 2 days. The mixture was quenched with water/THF at 0° C. carefully and water was added to form precipitates which were washed with EtOAc and water and dried in vacuo to give crude title compound (4.7 g). The part of this material (ca. 4.3 g) was crystallized from DMSO (200 mL)-EtOH (40 mL)/water (400 mL) to give 9-[4-(cyclohexyloxy)phenyl]-7-methyl-3,4-dihydropyrazino[2,1-c][1,2,4]thiadiazine 2,2-dioxide as light-yellow crystals (3.6 g), which was recrystallized from DMSO (100 mL)-EtOH (15 mL)/water (100 mL) at 80° C. to room temperature to give the title compound (3.09 g) as light-yellow crystals.

Provenance & Evidence