66315-16-0

General procedure for the synthesis of methyl 3-amino-4-(methylamino)benzoate from methyl 4-(methylamino)-3-nitrobenzoate: Methyl 4-(methylamino)-3-nitrobenzoate (540 mg, 2.5 mmol) was dissolved in a solvent mixture of ethyl acetate and methanol (2:1 v/v/v, 20 mL). A 10% palladium-carbon catalyst (5 mol%) was added to the solution under nitrogen protection. The reaction mixture was placed in a hydrogen atmosphere and the reaction was stirred for 4 hours. Upon completion of the reaction, the catalyst was removed by diatomaceous earth filtration. The filtrate was concentrated under reduced pressure to afford the target product methyl 3-amino-4-(methylamino)benzoate. The product was characterized by LC-MS with molecular ion peak [M + 1] = 181.1. yield: 441 mg (100% yield).

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