Benzyl mercaptan → 4-Benzylsulfanyl-5-nitro-thiophene-3-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

An aqueous solution of potassium carbonate (9.90 g, 71.6 mmol, dissolved in 40 mL water) was added to a suspension of 4-bromo-5-nitro-thiophene-3-carboxylic acid ethyl ester (20.06 g, 71.6 mmol) in ethanol at 25° C. Benzyl mercaptan (8.41 mL, 71.6 mmol) was added via pipette, and the dark red reaction mixture was stirred at 25° C. for 4 h and then was concentrated in vacuo to near-dryness. The remaining orange-brown solid was triturated with water (200 mL) and was collected by filtration. After washing with water (200 mL), the resulting solid was air-dried overnight to afford the desired product, 4-benzylsulfanyl-5-nitro-thiophene-3-carboxylic acid ethyl ester (22.63 g, 70.0 mmol, 98%), as a yellow/brown solid. 1H NMR (400 MHz, CDCl3) δ: 1.41 (3H, t, J=7.1 Hz), 4.25 (2H, s), 4.39 (2H, q, J=7.0 Hz), 7.18-7.23 (5H, m), 8.07 (1H, s).

Provenance & Evidence