Phosphorus oxychloride → 3-Chloro-2-(2,4-dichloro-6-fluorobenzothiazol-7-yl)-4,5,6,7-tetrahydro-2H-indazole

Participants

Reaction Steps

0.2 g 2-(2,4-Dichloro-6-fluorobenzothiazol-7-yl)1,3,4,5,6,7-hexahydro-2H-indazol-3-one was treated with 2 ml phosphorus oxychloride and the mixture stirred for one hour under reflux. After cooling, it was poured into ice-water, extracted with ethyl acetate and the organic phase washed with sodium hydrogen carbonate and water. It was dried over magnesium sulfate and concentrated. The residue was purified by column chromatography. Yield: 0.07 g=32% of theory m.p.: 161°-163° C.

Provenance & Evidence