N-Iodosuccinimide → 5-Iodoindolin-2-one

Participants

Reaction Conditions

Reaction Steps

2-Oxindole (82.9 g) was suspended in 630 ml of acetic acid in a reaction vessel equipped with mechanical stirring and the mixture cooled to 10° C. in an ice water bath. Solid N-iodosuccinimide (175 g) was added in portions over 10 minutes. After the addition was complete the mixture was stirred for 1 hour at 10° C. The suspended solid which was always present became very thick at this time. The solid was collected by vacuum filtration, washed with 100 ml of 50% acetic acid in water and then with 200 ml of water and subjected to vacuum filtration for 20 minutes to partially air dry it. The product was then dried under vacuum to give 93.5 g (36%) of 5-iodo-2-oxindole containing about 5% 2-oxindole by proton NMR.

Provenance & Evidence