Water → 2-Chloro-9-fluoro-3-phenylpyrimido[1,2-b]indazole

Participants

Reaction Steps

7.2 g (21.7 mmol) 2,4-Dichloro-9-fluoro-3-phenylpyrimido[1,2-b]indazole were suspended in a mixture of 551 mL ethanol, 392 mL water and 211 mL tetrahydrofuran. After addition of 5.5 g (102.7 mmol) ammonium chloride and 9.1 g (138.7 mmol) zinc the mixture was stirred over night at room temperature. The mixture was filtered via a glass fibre filter, and the organic solvents were removed. The product which precipitated was filtered off (3.4 g=51.9%). 3.4 g (42.2%) of the starting material wereregained by stirring the zinc slurry with 1 L ethyl acetate, filtration of the zinc via a glass fibre filter and evaporation of the organic solvent. The product was contaminated with 9-fluoro-3-phenylpyrimido[1,2-b]indazole (25%).

Provenance & Evidence