Trifluoroacetic acid → HCID 46317762, compound

Participants

Reaction Steps

Ethyl 3-[hydroxy(2-naphthyl)methyl]-5-pyridin-4-ylthiophene-2-carboxylate (118.0 mg, 0.3030 mmol), methylene chloride (2.4 mL), trifluoroacetic acid (140.0 uL, 1.818 mmol), and triethylsilane (84.7 uL, 0.530 mmol) were combined in a round bottomed flask equipped with a stirbar. The reaction was stirred overnight at room temperature under an atmosphere of nitrogen. An aliquot was taken from the reaction, quenched into water, basified with sodium carbonate, and extracted with ethyl acetate. TLC analysis (2:1 ethyl acetate:DCM) indicated that the starting ester was ˜50% converted to a slightly higher Rf product. Additional trifluoroacetic acid (300 uL, 4 mmol) and triethylsilane (200 uL, 1 mmol) were added and the reaction was stirred at room temperature under an atmosphere of nitrogen for another 4 hours. LCMS analysis showed one major peak with correct ES+ for product with a small amount of SM remaining. The reaction was quenched into water, basified, and extracted into ethyl acetate. The extract was washed with saline, dried over sodium sulfate, filtered, and evaporated to leave crude product as an oil. The crude product was dissolved in minimal DCM then was purified by column chromatography on silica gel (gradient 100% DCM to 50% ethyl acetate) to afford product 86 mg (76% yield) as a white solid. LC/MS (FA) ES+ 374. 1H NMR (400 MHz, DMSO) δ 8.64-8.55 (m, 2H), 7.90-7.80 (m, 4H), 7.80-7.75 (s, 1H), 7.73-7.66 (m, 2H), 7.52-7.40 (m, 3H), 4.57-4.49 (s, 2H), 4.39-4.27 (q, J=7.1 Hz, 2H), 1.35-1.25 (t, J=7.1 Hz, 3H).

Provenance & Evidence