264916-06-5

General procedure for the synthesis of tert-butyl 5-aminoisoindoline-2-carboxylate from tert-butyl 5-nitroisoindoline-2-carboxylate: In a 100 mL single-necked round-bottom flask equipped with a magnetic stirrer, tert-butyl 5-nitroisoindoline-2-carboxylate (650 mg, 2.5 mmol) and anhydrous ethanol (50 mL) were added. Palladium/carbon catalyst (160 mg) was added to the reaction mixture and the hydrogenation reaction was carried out at room temperature for 15 hours. Upon completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated under reduced pressure to afford the target product tert-butyl 5-aminoisoindole-2-carboxylate (585 mg, 99% yield) as a yellow oil. The product could be used in subsequent steps without further purification. Mass spectrometry result: [M + H]+ 179.

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