“…1 H NMR (500 MHz, CDCl 3 ): δ 11.85 (s, 1H), 7.49 (t, J = 7.8 Hz, 4H), 7.37 (t, J = 7.8 Hz, 6H), 3.22 (s, 6H), 2.59 (s, 6H) ppm. 13 ). Formazan (46.9 mg, 0.1 mmol) was dissolved in CH 3 OH (15 mL), and the solution was stirred for 15 min before Zn(CH 3 COO) 2 •2H 2 O (9.2 mg, 0.05 mmol) was added, and the solution was refluxed with stirring at 90 °C for 24 h under a nitrogen atmosphere.…”