Water → 2-(4-Bromobenzyl)isoindoline-1,3-dione

To a suspension of 10 g (44.94 mmol) of 4-bromobenzylamine hydrochloride in 200 ml of chloroform was added 12.5 ml (89.62 mmol) of triethylamine, followed by the addition of 8.99 g (60.67 mmol) of phthalic anhydride. The mixture was stirred at room temperature for 10 minutes to give a homogeneous solution, which was then heated at 75° C. for three hours. The reaction mixture was then evaporated to remove the chloroform and the residue was suspended in 400 ml of toluene followed by adding 700 mg of p-toluenesulfonic acid monohydrate. The resulting mixture was briefly refluxed at 140° C., and additional 3 ml of triethylamine was added to form a homogeneous solution. The solution was refluxed at 140° C. for 2 hours; and the water formed was collected through a Dean-Stark trap apparatus. The solution was then cooled to room temperature, washed with 3% sodium hydroxide (2×200 ml), water (1×200 ml), brine (1×200 ml), and dried over sodium sulfate. Removal of the solvent under reduced pressure gave 12.07 g (85% yield) of 4-phthalimidomethyl bromobenzene as a white solid. Rf: 0.6 (silica gel, ethyl acetate:hexane=1:2). 1H NMR (CDCl3): δ ppm 4.79 (2H, s), 7.31, 7.44 (2H each, AA'BB'), 7.73, 7.84 (2H each, m).

1. customto give a homogeneous solution, which
2. temperaturewas then heated at 75° C. for three hours
3. customThe reaction mixture was then evaporated
4. customto remove the chloroform
5. additionby adding 700 mg of p-toluenesulfonic acid monohydrate
6. temperatureThe resulting mixture was briefly refluxed at 140° C.
7. additionadditional 3 ml of triethylamine was added
8. customto form a homogeneous solution
9. temperatureThe solution was refluxed at 140° C. for 2 hours
10. customwas collected through a Dean-Stark trap apparatus
11. temperatureThe solution was then cooled to room temperature
12. washwashed with 3% sodium hydroxide (2×200 ml), water (1×200 ml), brine (1×200 ml)
13. dry with materialdried over sodium sulfate
14. customRemoval of the solvent under reduced pressure

ORD record

ord-cd62646435484865bb767022b00447e2

Source dataset

uspto-grants-2000_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06165800