反应详情

Sodium diatrizoate (16.1 g, 25.3 mmol) was dissolved in 180 ml of dry dimethylformamide and to this solution was added, in one portion, ethyl 6-bromohexanoate (4.5 ml, 25.3 mmol). The reaction mixture was stirred for 12 hr at ambient temperature and then poured into 1.6 1 of ice-water with stirring. The resulting white precipitate was collected by filtration, dissolved in 1:1 ethanol-ethyl acetate and the solution was treated sequentially with magnesium sulfate, decolorizing charcoal and then filtered through a short pad of silica gel. The filtrate was concentrated to dryness and dried to give 16 g (84%) of the desired product. Recrystallization from methanol-water gave analytically pure material, mp 235°-238° C. (decomp. at 275° C.); MS:M+ 756. The 1H-NMR (300 MHz) spectral data was consistent with the desired product. Calculated for C19H23I3N2O6 : C 30.18, H 3.07, I 50.35, N 3.70; Found: C 30.26, H 2.88, I 50.40, N 3.65.

1. stirringwith stirring
2. filtrationThe resulting white precipitate was collected by filtration
3. dissolutiondissolved in 1:1 ethanol-ethyl acetate
4. additionthe solution was treated sequentially with magnesium sulfate
5. filtrationfiltered through a short pad of silica gel
6. concentrationThe filtrate was concentrated to dryness
7. customdried