General procedure for the synthesis of the compound (CAS:77123-56-9) from 3-(trimethylsilyl)ethynylbenzaldehyde: Tetrabutylammonium fluoride (0.78 g, 3.0 mmol) was added batchwise to a solution of tetrahydrofuran (THF, 20 mL) containing 3-(trimethylsilyl)ethynylbenzaldehyde (0.30 g, 1.5 mmol) at room temperature. The reaction mixture was stirred continuously for 3 h at room temperature and then concentrated under vacuum. The residue was purified by column chromatography (eluent: ethyl acetate/petroleum ether, ratio tapered from 1/20 to 1/10) to afford the target compound (0.17 g, 88% yield) as a white solid.1H NMR (300 MHz, DMSO-d6) δ: 10.01 (s, 1H), 8.00 (s, 1H), 7.93 (d, J=7.7 Hz, 1H), 7.81 (d, J=7.8 Hz, 1H), 7.63 (t, J=7.7 Hz, 1H), 4.38 (s, 1H).
