Hydrochloric Acid → HCID 68997237, compound

Participants

Reaction Steps

Crude 4-[2-(1H-indazol-3-yl)vinyl]-3-nitrobenzoic acid (1.0 g, 3.2 mmol) obtained in Step 1 was dissolved in ethanol (30 mL) and the solution was added with tin (1.2 g, 9.7 mmol) and concentrated hydrochloric acid (7.0 mL), followed by reacting at 40° C. to obtain 3-amino-4-[2-(1H-indazol-3-yl)vinyl]benzoic acid. The crude product (0.65 g, 2.3 mmol) was added with xylene (20 mL), triethylamine (0.16 mL, 1.2 mmol), phthalic anhydride (0.41 g, 2.8 mmol) and molecular sieves 3A (0.65 mg), followed by heating at 140° C. for 4 hours. The reaction mixture was filtered and the filtrate was acidified by hydrochloric acid (2 mol/L). The precipitated crystal was collected by filtration to obtain 3-(1,3-dioxo-1,3-dihydroisoindol-2-yl)-4-[2-(1H-indazol-3-yl)vinyl]benzoic acid.

Provenance & Evidence