4-Nitro-N-methylphthalimide → 5-amino-2-methyl-2,3-dihydro-1H-isoindole-1,3-dione

Participants

Reaction Conditions

Reaction Steps

0.005 g of ammonium vanadate and 2.5 g 1% by weight of titanium dioxide extrudate containing metallic palladium and having a particle size of 3 mm (from Johnson Matthey) are added to a suspension consisting of 250 ml of water and 10.3 g of 4-nitro-N-methylphthalimide. After displacing the air with nitrogen, the latter is replaced by hydrogen at atmospheric pressure and the suspension is stirred at 63° C. for 75 hours. During this time, 104% of the theoretical amount of hydrogen, based on the 4-nitro-N-methylphthalimide, is absorbed. The resulting suspension is then sieved through a sieve having a mesh width of 1 mm. The material remaining on the sieve is washed with 50 ml of water and the combined aqueous phases are then filtered through a paper filter and washed with 50 ml of water. Drying at 80° C. under reduced pressure (125 mbar) gives 8.3 g (94%) of 4-amino-N-methylphthalimide. The purity determined by high pressure liquid chromatography is 98%.

Provenance & Evidence