反应详情

温度

50 °C

A mixture of methyl 5-methyl-4-nitrothiophene-2-carboxylate (95 g) and 10% palladium-carbon (50% containing water, 10 g) in tetrahydrofuran (250 mL)-methanol (250 mL) was stirred at 50° C. for 8 hr under a hydrogen atmosphere (0.3 MPa). The catalyst was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was crystallized from diethyl ether to give methyl 4-amino-5-methylthiophene-2-carboxylate (58 g, yield 72%) as yellow crystals. melting point 91° C.

1. filtrationThe catalyst was filtered off
2. concentrationthe filtrate was concentrated under reduced pressure
3. customThe obtained residue was crystallized from diethyl ether