2-Thiophenecarboxaldehyde, 5-chloro- → HCID 86607167, compound

Participants

Reaction Steps

A solution of N-(4-Amino-2-chlorophenyl)-2,2,2-trifluoroacetamide (4.567 g, 19.14 mmol) and 5-chloro-thiophene-2-carboxaldehyde (3.97 g, 27.1 mmol) in anhydrous ethanol (50 mL) was heated to reflux for 15 minutes and evaporated in vacuo at 70° C. (0.1 mbar, 30 min). The obtained crude imine as a crystalline solid was dissolved in methanol followed by addition of sodium cyanoborohydride (NaBH3CN) in methanol (50 mL) and acetic acid (9 mL) by portions. The obtained reaction mixture was stirred at room temperature for 60 minutes and evaporated in vacuo to small volume. The concentrated solution was quenched with water and filtered after 30 minutes to give 6.98 g (99% yield) of the title compound as a brown-yellow solid. 1H NMR (DMSO-d6): 4.43 (d, 2H), 6.63 (dd, 1H), 6.77 (d, 1H), 6.79 (t, 1H, NH), 6.94 (d, 1H), 6.97 (d, 1H), 7.10 (d, 1H), 10.85 (br. s, 1H, NHCO). LC/MS (m/z) 367.9 (M+); RT=3.36, (UV, ELSD) 99%, 100%.

Provenance & Evidence