Reaction Steps
Prepared according to the general procedure using (Z)-4-benzylidene-2-(2-fluorophenyl)-1H-imidazol-5(4H)-one and trans-cinnamaldehyde. After 72 h, the unpurified residue was purified by flash chromatography using 15% EtOAc/hexanes to afford 5h as an off-white solid (78 mg, 65%). Analytical data for 5 h: 1H NMR (500 MHz, CDCl3) δ 9.32 (d, J=8.4 Hz, 1H), 8.21 (td, J=8.0, 1.9 Hz, 1H), 7.36-7.21 (m, 8H), 7.12-7.05 (m, 3H), 7.02-6.99 (m, 2H), 4.09 (d, J=6.8 Hz, 1H), 3.62 (ddd, J=10.2, 6.8, 4.6 Hz, 1H), 3.37 (dd, J=14.9, 4.5 Hz, 1H), 2.43 (dd, J=14.8, 10.2 Hz, 1H); 13C NMR (CDCl3, 126 MHz) δ 169.1, 159.5 (d, JCF=244.7 Hz), 148.8, 138.0, 137.5, 137.2, 130.1 (d, JCF=8.9 Hz), 129.2, 129.0, 128.6, 128.5 (d, JCF=3.0 Hz), 128.2, 128.0, 126.7, 125.2 (d, JCF=2.9 Hz), 117.0 (d, JCF=10.2 Hz), 115.8 (d, JCF 22.3 Hz), 110.3 (d, JCF=3.3 Hz), 47.4, 38.4, 32.7; IR (film) cm−1 1771, 1632, 1614, 1528, 1467, 1454, 1428, 1122, 1106, 1073, 909, 762, 732, 698; LRMS (ESI): Mass calcd for [M+H]+ C25H20FN2O2: 399.1. found 399.4; Enantiomeric ratio was measured by chiral phase HPLC (Chiralcel OD-H; 5% IPA/3% MeOH/hexanes 0.5 mL/min, 280 nm), Rt1 (minor)=53.0, Rt2 (major)=63.6 min; er=98:2.
