## 2 Materials and Methods
### General Procedure for Synthesis of Fluorinated Pyrazoles (**3a-j**)
); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (ppm): 164.2, 162.5, 159.6, 159.5, 155.2, 142.8, 129.9, 129.1 (d, \(J\) = 2.40 Hz), 127.3, 117.5, 115.9, 115.8, 112.7, 111.6, 58.5, 52.0, 42.4; _m/z_ calcd for [C\({}_{17}\)H\({}_{15}\)FN\({}_{2}\)O]+ ([M+H]+/M++H+Na): 298.31, found 299.0/321.20. 3-(4-fluorophenyl)-5-(2-hydroxyphenyl)-4,5-dihydro-1H-pyrazol-1-carbaldehyde (3f)  
Mp = 204-206 \({}^{\circ}\)C; Rf = 0.74; \({}^{1}\)H NMR (300 MHz, ppm, DMSO-\(d_{6}\)): 9.74 (s, 1H, OH), 8.91 (s, 1H, \(-\)CHO); 7.85-7.80 (m, 2H, arom. ), 7.32-7.26 (m, 2H, arom. ), 7.33-7.31 (m, 2H, arom. ), 7.12-7.07 (t, 1H, arom. ), 6.95-6.92 (d, 1H, arom. ), 6.86-6.83 (d, 1H, arom. ), 6.76-6.71 (t, 1H, arom. ), 5.64-5.58 (m, 1H, CH-pyr. ), 3.90-3.80 (m, 1H, \(-\)CH\({}_{2}\)-pyr. ), 3.12-3.05 (m, 1H, CH\({}_{2}\)-pyr. ); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (ppm): 165.4, 162.1, 160.0, 156.1, 154.6, 129.5 (d, \(J\) = 8.78 Hz), 128.9, 128.1, 128.0, 127.0, 126.8, 119.3, 116.5, 116.2, 115.9, 53.4; _m/z_ calcd for [C\({}_{16}\)H\({}_{13}\)FN\({}_{2}\)O\({}_{2}\)]+ (M++H+Na): 284.29, found 307.22. 5-(2,5-dimethoxyphenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-carbaldehyde (3g)  
Mp = 153 \({}^{\circ}\)C; Rf = 0.82; \({}^{1}\)H NMR (300 MHz, ppm, DMSO-\(d_{6}\)): 8.91 (s, 1H, \(-\)CHO); 7.84-7.82 (m, 2H, arom. ), 7.31-7.28 (m, 2H, arom. ), 6.99-6.97 (d, 1H, arom. ), 6.85-6.83 (d, 1H, arom. ), 6.56-6.55 (d, 1H, arom. ), 5.61-5.58 (m, 1H, CH-pyr. ), 3.88-3.83 (m, 1H, \(-\)CH\({}_{2}\)-pyr. ), 3.75 (s, 3H, OCR\({}_{3}\)), 3.66 (s, 3H, OCR\({}_{3}\)), 3.08-3.05 (m, 1H, CH\({}_{2}\)-pyr. ); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (ppm): 164.1, 162.5, 159.6, 155.6, 153.1, 150.0, 130.0, 129.4, 129.0 (d, \(J\) = 9.61 Hz), 127.5, 115.9, 115.8, 112.7, 112.5 (d, \(J\) = 13.22 Hz), 56.0, 55.3, 54.6, 41.3; _m/z_ calcd for [C\({}_{18}\)H\({}_{17}\)FN\({}_{2}\)O\({}_{3}\)]+ (M++H+Na): 328.34, found 351.20. 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-carbaldehyde (3h)  
Mp = 144 \({}^{\circ}\)C; Rf = 0.85; \({}^{1}\)H NMR (300 MHz, ppm, DMSO-\(d_{6}\)): 8.89 (s, 1H, \(-\)CHO); 7.85-7.83 (m, 2H, arom. ), 7.55-7.53 (d, 2H, arom. ), 7.33-7.30 (m, 2H, arom. ), 7.22-7.20 (d, 2H, arom. ), 5.55-5.52 (m, 1H, CH-pyr. ), 3.94-3.89 (m, 1H, \(-\)CH\({}_{2}\)-pyr. ), 3.25-3.21 (m, 1H, CH\({}_{2}\)-pyr. ); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (ppm): 164.2, 162.5, 159.7, 155.2, 140.6, 131.6, 129.2, 129.1, 128.1, 127.3, 120.5, 115.9, 115.8, 58.1, 42.1; _m/z_ calcd for [C\({}_{16}\)H\({}_{12}\)BrFN\({}_{2}\)O]+ (M++H+Na): 347.18, found 369.00. 5-(2-chlorophenylophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-carbaldehyde (3i)  
Mp = 125-127 \({}^{\circ}\)C; Rf = 0.86; \({}^{1}\)H 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, \(-\)CH\({}_{2}\)-pyr. ), 3.19-3.12 (m, 1H, CH\({}_{2}\)-pyr. ); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (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 [C\({}_{16}\)H\({}_{12}\)ClFN\({}_{2}\)O]+ ([M++H]+/M++H+Na): 302.73, found 3032.0/325.10. 5-(4-(dimethylamino)phenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-carbaldehyde (3j)  
Mp = 168-171 \({}^{\circ}\)C; Rf = 0.13; \({}^{1}\)H NMR (300 MHz, ppm, DMSO-\(d_{6}\)): 8.86 (s, 1H, \(-\)CHO); 7.86-7.83 (m, 2H, arom. ), 7.33-7.30 (m, 2H, arom. ), 7.05-7.04 (d, 2H, arom. ), 6.68-6.66 (d, 2H, arom. ), 5.43-5.40 (m, 1H, CH-pyr. ), 3.87-3.82 (m, 1H, \(-\)CH\({}_{2}\)-pyr. ), 3.19-3.16 (m, 1H, CH\({}_{2}\)-pyr. ), 2.86 (s, 6H, 2 CH\({}_{3}\)); \({}^{13}\)C NMR (DMSO-\(d_{6}\)) \(\delta\) (ppm): 164.2, 162.5, 159.4, 155.1, 149.9, 129.0, 128.9, 128.7, 127.5, 126.5, 115.9, 115.8, 112.4, 58.3, 42.2, 40.1; _m/z_ calcd for [C\({}_{18}\)H\({}_{18}\)FN\({}_{3}\)O]+ ([M++H]+/M++H+Na): 311.35, found 312.30/334.