反应详情

A solution of 3-fluoroaniline (1.67 g, 15 mmole) in 17 mL of water, acidified with 3.75 mL of conc. HCl (45 mmole) in an ice bath, was treated with NaNO2 (1.35 g, 19.5 mmole). The diazonium solution was then added to the solution of 4-(1,3-dioxo-1,3-dihydroisoindol-2-yl)-3-oxobutyronitrile (2.28 g, 10 mmole) with NaOAc (6.12 g, 45 mmole) in DMF/water mixture (30:35 mL). From this reaction, 3.4 g of 2-{5-amino-4-[(3-fluorophenyl)hydrazono]-4H-pyrazol-3-ylmethyl}isoindole-1,3-dione, as a yellow powder, was obtained, which was then treated with hydrazine (22 mmole) portionwise in hot ethanol. After the reaction was completed, a few grams of silica gel was mixed and the solvent was evaporated. The powdery residue was purified by column chromatography (CH2Cl2:MeOH:NH3.H2O=600:150:6) to yield 1.5 g (61%) of the title compound as an orange powder. 1H NMR (ppm, 200 MHz, DMSO-d6) δ 7.40-7.70 (m, 3H), 7.12 (m, 1H), 7.00 (br s, 2H), 4.01 (s, 2H).

1. customas a yellow powder, was obtained
2. additiona few grams of silica gel was mixed
3. customthe solvent was evaporated
4. customThe powdery residue was purified by column chromatography (CH2Cl2:MeOH:NH3.H2O=600:150:6)