Water → N-(4-Bromobutyl)phthalimide

Temperature

90 °C

To a hot solution (90° C.) of dibromobutane (1.50 kg, 6.95 mol) in dimethylformamide (1.7 L) was added potassium phthalimide (329 g, 1.74 mol). The solution was stirred at 90° C. for 5 hours. The solution was cooled to room temperature prior to the addition of water (900 mL). The layers were separated and the aqueous layer was extracted with CH2Cl2 (2×500 mL). The combined organic portions were washed with a saturated aqueous solution of NaHCO3 (1.0 L). The organic layer was dried (MgSO4) and concentrated under reduced pressure. Hexane (3.0 L) was added to the residue and the solid (mostly diphthalimide side product) was filtered. Hexane (1.0 L) was added to the filtrate and the resulting mixture was placed at −20° C. for 1.5 hours. the precipitate was filtered and dried under vacuum to afford 285 g (58%) of 2-(4-bromo-butyl)-isoindole-1,3-dione as white solid. 1H NMR (CDCl3) δ 1.75-7.95 (m, 4H), 3.44 (t, 2H, J=6.5 Hz), 3.71 (t, 2H, J=6.5 Hz), 7.65-7.75 (m, 2H), 7.80-7.90 (m, 2H). 13C NMR (CDCl3) δ 27.64, 30.22, 33.26, 37.35, 123.68, 132.42, 134.42, 168.79.

1. temperatureThe solution was cooled to room temperature
2. customThe layers were separated
3. extractionthe aqueous layer was extracted with CH2Cl2 (2×500 mL)
4. washThe combined organic portions were washed with a saturated aqueous solution of NaHCO3 (1.0 L)
5. dry with materialThe organic layer was dried (MgSO4)
6. concentrationconcentrated under reduced pressure
7. additionHexane (3.0 L) was added to the residue
8. filtrationthe solid (mostly diphthalimide side product) was filtered
9. additionHexane (1.0 L) was added to the filtrate
10. waitthe resulting mixture was placed at −20° C. for 1.5 hours
11. filtrationthe precipitate was filtered
12. customdried under vacuum

ORD record

ord-5c5da8fd01ab4a5194e715aeb5dde30c

Source dataset

uspto-grants-2009_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07501518B2