56341-39-0

6-Fluorooxindole, also known as 6-Fluoro-2-oxindole, is a fluorinated organic heterocyclic compound that can be used in the preparation of pharmaceutical and chemical products.

The general procedure for the synthesis of 6-fluoroindolin-2-one from 2-(4-fluoro-2-nitrophenyl)acetic acid is as follows: 119 g of 2-(4-fluoro-2-nitrophenyl)acetic acid (Feedstock III) and 600 ml of acetic acid were added to a reactor followed by 20 g of palladium catalyst (loaded on 10% activated carbon). The hydrogenation reaction was carried out under hydrogen pressure of 50 psi. Upon completion of the reaction, the catalyst was removed by diafiltration, followed by removal of the solvent acetic acid by distillation. The crude product obtained was co-milled with 500 ml of petroleum ether, further separated by diafiltration, washed with water and dried. Finally 82.5 g of 6-fluoroindolin-2-one was obtained in 91% yield of the theoretical value. The product was detected by thin layer chromatography (TLC) with an Rf value of 0.30 (silica gel plate, unfolding agent was petroleum ether/ethyl acetate 1:1). Mass spectrometry analysis showed a molecular ion peak m/z = 150 [MH]-, which is consistent with the molecular weight of the target product C8H6FNO.

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