反应详情

To a 35° C. mixture of 50 g of 2-methyl-5-nitrobenzofuran, ethanol (250 mL), THF (250 mL) and wet 10% Pd/C (4 g) was added ammonium formate (53.4 g, 0.85 mol) over 50 min. After an additional 4 h, the reaction was cooled to room temperature and filtered through Celite. The filtrate was concentrated and the residue was taken up in methyl t-butyl ether. This mixture was filtered, concentrated and dried to provide 2-methyl-5-benzofuranamine which was converted to its hydrochloride salt or its oxalate salt. The oxalate was prepared as follows: To a solution of 2-methyl-5-benzofuranamine in TBME (415 mL) was added a solution of oxalic acid (25.4 g) in methanol (80 mL) dropwise. The precipitate was stirred for 2 h, collected, washed with methanol/TBME and dried to provide 2-methyl-5-benzofuranamine oxalate.

1. filtrationfiltered through Celite
2. concentrationThe filtrate was concentrated
3. filtrationThis mixture was filtered
4. concentrationconcentrated
5. customdried