Hydrochloric Acid → {4-[6-(2-Piperidin-4-yl-(E)-vinyl)-1H-indazol-3-yl]-piperidin-1-yl}-acetic acid, hydrochloride hydrate

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Reaction Steps

A suspension of {4-[6-(2-piperidin-4-yl-(E)-vinyl)-1H-indazol-3-yl]-piperidin-1-yl}-acetic acid (20.5 g) in water (41 ml) was carefully adjusted to pH 5.7 with 2M hydrochloric acid (27 ml). The resulting solution was filtered through 1 micron graded glass fibre filter paper and the filter washed through with water (2×20.5 ml). Isopropanol (219 ml) was added dropwise to the stirred filtrate over 0.25 h at 22°, and the solution was seeded with product crystals (10 mg). The mixture was allowed to crystallise for 0.5 h, stirred at 22° for 1.5 h, and further isopropanol (219 ml) was added slowly over 0.5 h. After stirring for a further 3 h at 22° the suspension was filtered. The filter cake was washed with a mixture of isopropanol:water (4:1, 2×41 ml) and dried in vacuo at 45° for 6 h to give the title compound as a white solid (14.1 g).

Provenance & Evidence