2-Thiophenecarbonyl chloride → HCID 71230583, compound

Participants

Reaction Steps

Intermediate C (146 mg, 0.372 mmol) was dissolved in dry CH2Cl2 (3 ml), 2-thiophenecarbonyl chloride (92 μL, 0.856 mmol) and AlCl3 (114 mg, 0.856 mmol) were added and the mixture was sealed under Ar-atmosphere. After 26 hrs, the reaction was diluted with CH2Cl2 (10 ml), washed with water (20 ml) and the aqueous layer was subsequently washed with CH2Cl2 (10 ml×2). The organic layers were combined and evaporated to dryness to obtain the crude product. The residue was purified by flash chromatography using toluene/EtOAc (19:1→9:1→6:1) as eluent to first obtain the monoacylated product methyl 2-(2-{5-[3-(2-methoxy-2-oxoethyl)-5-(thiophene-2-carbonyl)thiophen-2-yl]thiophen-2-yl}thiophen-3-yl)acetate Yield: 63 mg (34%). 1H NMR (400 MHz, CDCl3): δ 3.75 (s, 3H), 3.77 (s, 3H), 3.81 (s, 2H), 3.87 (s, 2H), 7.08 (d, J 4.0 Hz, 1H), 7.20-7.23 (m, 2H), 7.29-7.31 (m, 2H), 7.72 (dd, J 2.0, 4.0 Hz, 1H), 7.87 (s, 1H), 7.94 (dd, J 2.0, 4.0 Hz, 1H). Second eluted compound; the diacylated product methyl 2-(2-{5-[3-(2-methoxy-2-oxoethyl)-5-(thiophene-2-carbonyl)thiophen-2-yl]thiophen-2-yl}-5-(thiophene-2-carbonyl)thiophen-3-yl)acetate. Yield: 90 mg (39%) 1H NMR (400 MHz, CDCl3): δ 3.79 (s, 6H), 3.87 (s, 4H), 7.23 (dd, J 4.0, 4.0 Hz, 2H), 7.36 (s, 2H), 7.73 (dd, J 2.0, 4.0 Hz, 2H), 7.88 (s, 2H), 7.94 (dd, J 2.0, 4.0, 2H).

Provenance & Evidence