Palladium oxide on charcoal

Methoxycarboxyl-5-nitrobenzoic acid (25 g) was hydrogenated in methanol (500 ml) using palladium oxide on charcoal (2.5 g 10%) at atmospheric pressure. When the exothermic reaction was completed the catalyst was fluttered off. After cooling the solution at -20°C for 2.5 h, 12.7 g of 3-amino-5-methoxycarbonylbenzoic acid was isolated. An additional 6.5 g of it was isolated by concentrating the mother liquor. 

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