Trifluoroacetic acid → HCID 66625194, compound

Participants

Reaction Steps

This compound can be synthesized either step-wise or one-pot. Step-wise formation was achieved by adding 5-(thiophen-2-yl)thiophene-2-carbaldehyde (30 mg, 0.15 mmol) to diethyl 2,5-diaminothiophene-3,4-dicarboxylate (48 mg, 0.19 mmol) followed by refluxing in isopropanol for 12 hours with a catalytic amount of TFA. The intermediate product was isolated as a yellow powder 3 (50 mg, 1.1 mmol 74%) after purification by flash chromatography. To the resulting product was added 2-thiophene carboxaldehyde (13 mg, 1.2 mmol) in isopropanol with a catalytic amount of TFA. The reaction was refluxed for 12 hours. The title product was isolated as a red colored powder following flash chromatography (37.5 mg, 0.1 mmol, 46%). 1H-NMR (400 MHz, [D] acetone): δ=8.75 (s, 1H), 8.69 (d, 1H, 3J=3.6), 7.86 (d, 1H, 3J=4.96), 7.78 (d, 1H, 3J=2.84), 7.71 (d, 1H, 3J=3.88), 7.59 (dd, 1H, 3J=5.04, 4J=0.76), 7.51 (d, 1H, 3J=3.68), 7.26 (dd, 1H, 3J=3.76, 4J=1.2), 7.17 (dd, 1H, 3J=3.68, 4J=1.36), 4.35 (m, 4H), 1.40 (m, 6H).

Provenance & Evidence