Trifluoroacetic acid → 5-(4-Nitro-benzyl)-1,3-dihydro-indol-2-one

Participants

Reaction Steps

In a dried 250 mL round bottom flask, 20.73 mL of trifluoroacetic acid was added and then cooled to 0° C. under Ar(g). NaBH4 in pellet form (1.35 g, 35.71 mmol, ˜1.5 pellets) was added to the flask. 5-(4-Nitro-benzoyl)-1,3-dihydro-indol-2-one (as prepared in Example 7, 1.0 g, 3.55 mmol) was then added in slowly over 15 min. After the addition was completed, the reaction was allowed to warm to room temperature and was stirred for 36 hours forming a yellow foamy mixture. The mixture was poured over ice-water and allowed to warm to room temperature, during which a tan solid precipitated out of solution. The tan solid was collected by filtration and washed with water affording 5-(4-Nitro-benzyl)-1,3-dihydro-indol-2-one in 61% yield (0.589 g, 2.165 mmol).

Provenance & Evidence