Reaction Steps
A solution of (E)-4-(4-(trifluoromethoxy)-phenyl)-but-3-en-2-one (623 mg, 2.7 mmol) in EtOH (10 mL) was stirred for 5 min at 0° C. A solution of K2CO3 (748 mg, 5.4 mmol) in H2O (4 mL) was added and the reaction mixture was stirred for further 1 h. After the dropwise addition of 4-(trifluoromethyl)-benzaldehyde (392 μl, 2.9 mmol), the mixture was continued to stir for 4 h at 0° C. and for 2 h at ambient temperature. The resulting yellow precipitate was filtered and dried in vacuo to obtain NW337 as a pale yellow solid (337 mg, 34%). mp: 97-99° C. 1H NMR (300 MHz, CDCl3) δ (ppm): 7.76 (d, 3J=16.1 Hz, 1H, Hvin), 7.75 (d, 3J=15.7 Hz, 1H, Hvin), 7.74 (d, 3J=8.8 Hz, 2H, HAr), 7.69 (d, 3J=8.1 Hz, 2H, HAr), 7.67 (d, 3J=8.7 Hz, 2H, HAr), 7.29 (d, 3J=8.0 Hz, 2H, HAr), 7.15 (d, 3J=16.0 Hz, 1H, Hvin), 7.07 (d, 3J=16.0 Hz, 1H, Hvin). 13C NMR (75 MHz, CDCl3) δ (ppm): 188.2 (C), 150.7 (C), 142.1 (CH), 141.6 (CH), 138.1 (q, 4J(C, F)=1.3 Hz, CH), 133.2 (C), 132.0 (q, 2J(C, F)=32.7 Hz, C), 129.9 (CH), 128.5 (CH), 127.3 (CH), 126.0 (q, 3J(C, F)=3.8 Hz, CH), 125.9 (CH), 122.1 (C), 122.0 (C), 121.2 (CH), 118.7 (C). MS (FAB) m/z: 387.1 (M+). Anal. calcd for C19H12F6O2.0.5H2O: C, 57.73; H, 3.31. Found: C, 57.75; H, 3.20%.
