Acetic Acid → HCID 20569894, compound

Participants

Reaction Steps

1-(4-Hydroxypiperidino)-6,7-dimethoxyphthalazine (1.45 g), (prepared as in Example 2), acetic anhydride (1.5 g) and acetic acid (12 ml) were heated together at 90° for 17 hours. The cooled solution was then diluted with water (20 ml), basified with sodium carbonate to pH 10, and extracted with chloroform (2×50 ml). The chloroform extract was washed (H2O), dried (MgSO4), and evaporated in vacuo to give a dark oil. The oil was applied to the top of a column of powdered silica (bed size 30×2.0 cm) and eluted with chloroform containing increasing percentages (up to 30%) of methanol. Of fifteen fractions (each of 100 ml) collected, fractions 11-13 were combined and evaporated in vacuo to give an oily residue which was triturated with ether (60 ml). After removing insoluble material by filtration, the ethereal solution was treated with ethereal oxalic acid to pH 4 to precipitate the gelatinous oxalate salt. Recrystallization from ethanol gave pink crystals of 1 -(4-acetoxypiperidino)-6,7-dimethoxy phthalazine monooxalate (120 mg), m.p. 212°-13°.

Provenance & Evidence