Hydrochloric Acid → 2-chloro-6H-thiazolo[4,5-d]pyridazin-7-one

Participants

Reaction Steps

The compound (822 mg) obtained in Step 5 was suspended in 6N aqueous hydrochloric acid solution (6.6 ml), and sodium nitrite (1.69 g) was added in several portions at room temperature. After stirring the obtained suspension at room temperature for 30 min, the reaction mixture was diluted with water, and the solid was collected by filtration, washed with water and a small amount of acetone, and dried to give the title compound (770 mg).

Provenance & Evidence