33890-03-8

Off-white powder

General procedure: 4-nitroisophthalic acid (98 g, 0.457 mol) was dissolved in methanol (5 L) and 20% Pd/C catalyst was added. The hydrogenation reaction was carried out at room temperature for 4 hours. Upon completion of the reaction, the mixture was filtered through diatomaceous earth to remove the catalyst. The filtrate was concentrated in vacuum to afford 4-aminoisophthalic acid (72 g, 87% yield) as a white solid. The product was detected by thin layer chromatography (TLC) with chloroform/methanol (7:3) as the unfolding agent and an Rf value of 0.4.

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