5-Methyl-4-nitro-thiophene-2-carboxylic acid benzyl ester → 5-Methyl-4-amino-thiophene-2-carboxylic acid benzyl ester

Participants

Reaction Steps

Sponge nickel (0.6 g water wet) was added to a solution of 5-methyl-4-nitro-thiophene-2-carboxylic acid benzyl ester (0.93 g, 3.4 mmol), prepared as described in Step 1 above, in tetrahydrofuran (50 mL), and the mixture was hydrogenated at room temperature under hydrogen atmosphere at a starting pressure of 50 psi. After a reaction time of 2.4 hours, the pressure was released and the mixture filtered. The slurry was rinsed with tetrahydrofuran, and the filtrate was stripped of solvent under reduced pressure, leaving 0.9 g of 5-methyl-4-amino-thiophene-2-carboxylic acid benzyl ester as an oil.

Provenance & Evidence