反应详情

The reaction was run at 0° C. for 20 h with stirring using (E)-4-((benzhydrylimino)methyl)benzonitrile (296 mg, 1.0 mmol, 1.0 equiv) and 10 mol % of (S)—N-benzhydryl-2-(3-(3,5-bis(trifluoromethyl)phenyl)thioureido)-N,3,3-trimethyl butanamide (4e). The product was subjected to purification by flash column chromatography (9:1, hexanes:Et2O) to afford (R)-4-((benzhydrylamino) (cyano)methyl)benzonitrile (310 mg, 0.96 mmol, 96% yield) as a white solid. The enantiomeric excess was determined to be 93% by chiral HPLC analysis (OD-H, 5.0% IPA in hexanes, 1.0 mL/min, 230 nm, tR(major)=41.1 min, tR(minor)=56.4 min); [α]D24=+27.3° (c=1.0, CHCl3). 1H NMR (500 MHz, CDCl3): δ 7.72 (4H, s), 7.57 (2H, d, J=7.5 Hz), 7.45 (2H, d, J=7.5 Hz), 7.39 (2H, t, J=7.8 Hz), 7.29-7.34 (3H, m), 7.23-7.27 (1H, m), 5.25 (1H, s), 4.67 (1H, br s), 2.25 (1H, br s). 13C {1H} NMR (125 MHz, CDCl3): δ 142.2, 140.5, 139.7, 132.7, 129.1, 128.8, 128.2, 128.0, 127.9, 127.4, 127.0, 118.1, 117.7, 113.1, 65.7, 52.0. IR (cm−1): 3310 (m), 3296 (m), 3025 (w), 2925 (w), 2845 (w), 2232 (m), 1609 (w), 1492 (m), 1453 (m), 1349 (m), 1189 (m), 925 (m), 746 (s), 703 (s).

1. customThe product was subjected to purification by flash column chromatography (9:1, hexanes:Et2O)