Reaction Steps
Prepared according to the general procedure using (Z)-4-benzylidene-2-(2,5-difluorophenyl)-1H-imidazol-5(4H)-one and (E)-3-(naphthalen-2-yl)acrylaldehyde. The unpurified residue was purified by flash chromatography using 15% EtOAc/hexanes to afford 15 as an off-white solid (99 mg, 71%). Analytical data for 15: 1H NMR (500 MHz, CDCl3) δ 9.35 (d, J=8.3 Hz, 1H), 7.89 (ddd, J=9.2, 6.1, 3.3 Hz, 1H), 7.86-7.80 (m, 2H), 7.78-7.74 (m, 1H), 7.53-7.45 (m, 3H), 7.38-7.32 (m, 3H), 7.24 (dd, J=8.5, 1.8 Hz, 1H), 7.07-6.92 (m, 4H), 4.08 (d, J=6.8 Hz, 1H), 3.74 (ddd, J=10.4, 6.8, 4.5 Hz, 1H), 3.54 (dd, J=14.8, 4.5 Hz, 1H), 2.60 (dd, J=14.9, 10.3 Hz, 1H); 13C NMR (CDCl3, 126 MHz) δ 168.9, 159.1 (d, JCF=243.3 Hz), 155.3 (d, JCF=241.8 Hz), 148.9, 137.1, 136.4, 135.2, 133.4, 132.3, 129.2, 128.4, 128.4, 128.1, 127.8, 127.7, 127.4, 127.0, 126.3, 125.7, 118.4 (dd, JCF=12.5, 8.9 Hz), 117.1 (dd, JCF=25.6, 8.7 Hz), 116.6 (dd, JCF=24.9, 9.9 Hz), 114.5 (dd, JCF=26.8, 3.9 Hz), 111.0 (d, JCF=3.7 Hz), 47.1, 38.4, 32.9; IR (film) cm−1 3057, 3030, 1770, 1635, 1619, 1530, 1481, 1411, 1172, 1116, 1104, 1032, 814, 766, 738, 701; LRMS (ESI): Mass calcd for [M+H]+ C29H21F2N2O2: 467.2. found 467.4; Enantiomeric ratio was measured by chiral phase HPLC (Chiralcel AD-H; 7% IPA/hexanes 1.0 mL/min, 230 nm), Rt1 (major)=37.8, Rt2 (minor)=48.3 min; er=96:4.
