反应详情

4-[1,3-Dihydro-1,3-dioxo-2H-isoindol-2-yl]butanal diethyl acetal (11.6 g) was added with vigorous stirring to a solution of 4-bromophenylhydrazine hydrochloride (9.0 g) in 50% aqueous acetic acid (370 ml). The mixture was heated on a steam bath for 4 hours and was then diluted with water, while still hot, to 1 l. The mixture was cooled and an orange yellow precipitate was filtered off and dried in vacuo. The solid was boiled in ethanol (250 ml) for 1 hour and residual solid filtered off and dried to afford the title compound as a yellow solid (9.5 g) m.p. 206°-209° C. Crystallisation of a portion of this solid (0.5 g) from ethanol (25 ml) gave a sample (0.25 g) m.p. 208°-212° C.

1. temperatureThe mixture was heated on a steam bath for 4 hours
2. temperatureThe mixture was cooled
3. filtrationan orange yellow precipitate was filtered off
4. customdried in vacuo
5. filtrationresidual solid filtered off
6. customdried