Methyl 5-methyl-4-nitrothiophene-2-carboxylate → Methyl 4-amino-5-methylthiophene-2-carboxylate

Participants

Reaction Steps

To a solution of methyl 5-methyl-4-nitrothiophene-2-carboxylate (F-3) (14.8 g, 73.6 mmol) in MeOH/THF (1:1, 300 mL) was added Raney Ni. The reaction mixture was degassed and charged with hydrogen 3 times, and then stirred at room temperature for 36 h under 1 atmosphere of hydrogen. Raney Ni was filtered, and the filtrate was concentrated. The residue was treated with aqueous HCl (1 N, 150 mL) and filtered. The filtrate was treated with aqueous NaOH (1 N) to bring pH to about 8 to 9. Then the mixture was extracted with ethyl acetate. The combined organic layers were dried over Na2SO4, and the solvent was removed to give the title compound (8.1 g).

Provenance & Evidence