Phthalic Anhydride → 2-[3,5-Dichloro-4-(5-isopropyl-6-oxo-1,6-dihydro-pyridazin-3-ylmethyl)-phenyl]-isoindole-1,3-dione

Participants

Reaction Conditions

Reaction Steps

A solution of 6-(4-amino-2,6-dichloro-benzyl)-4-isopropyl-2H-pyridazin-3-one (910 mg, 2.90 mmol) in glacial acetic acid (12 mL) was treated with phthalic anhydride (430 mg, 2.9 mmol). The reaction was then heated to 130° C. for 3.5 h. At this time, the reaction was poured onto water (200 mL) and extracted into ethyl acetate (300 mL). The organics were then washed with water, dried with magnesium sulfate, filtered and concentrated under vacuum. The resulting orange solid was slurried in cold acetonitrile, collected by filtration, washed with cold acetonitrile and dried under vacuum to afford 2-[3,5-dichloro-4-(5-isopropyl-6-oxo-1,6-dihydro-pyridazin-3-ylmethyl)-phenyl]-isoindole-1,3-dione (92) (780 mg, 61%) as a light, tan solid; ES(+)-LRMS for C22H17Cl2N3O3 (M+H)+ at m/z=442. Exact Mass=441.0647; Molecular Weight=442.3051

Provenance & Evidence