*5-(2-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (***3i***)*

Mp = 125–127 ◦C; Rf = 0.86; 1H NMR (300 MHz, ppm, DMSO-*d*6): 8.96 (s, 1H, −CHO); 7.87–7.82 (m, 2H, arom.), 7.53–7.50 (m, 1H, arom.), 7.34–7.28 (m, 4H, arom.), 7.17–7.14 (m, 1H, arom.), 5.79–5.73 (m, 1H, CH-pyr.), 4.06–3.96 (m, 1H, −CH2-pyr.), 3.19–3.12 (m, 1H, CH2-pyr.); 13C NMR (DMSO-*d*6) δ (ppm): 165.5, 162,2, 160,1, 155.8, 138.3, 131.4, 130.2, 129.7, 129.6, 129.5, 128.2, 127.2, 116.5, 116.2, 56.9, 41.8; *m*/*z* calcd for [C16H12ClFN2O]+ ([M+H]+/M++H+Na): 302.73, found 303.20/325.10.
