(E)-3-(4-Methoxy-phenyl)-but-2-enoic acid ethyl ester → 61292-83-9

Participants

Reaction Steps

According to the general procedure, a solution of ethyl 3-(4-methoxyphenyl)but-2-enoate (58 mg, 0.26 mmol) and iridium catalyst (S)-32 (8.4 mg, 0.0053 mmol, 2 mol %) in CH2Cl2 (3 mL) was hydrogenated. Removal of the solvent in vacuo and standard purification gave 35 (58 mg, 99%) as a colorless oil; [α]20D −26.7 (c 1.00, CHCl3); CSP HPLC analysis (Chiralcel OB-H; eluent: 99.5:0.5 hexanes/i-PrOH, 0.5 mL/min) determined a 96:4 er (92% ee) [tR(major) 21.73 min, tR(minor) 28.91 min]; 1H NMR (300 MHz, CDCl3) 7.14 (d, 2H, J=8.4 Hz), 6.84 (d, 2H, J=8.7 Hz), 4.07 (q, 2H, J=6.9 Hz), 3.78 (s, 3H), 3.24 (sextet, 1H, J=7.2 Hz), 2.61-2.46 (m, 2H), 1.27 (d, 3H, J=6.9 Hz), 1.18 (t, 3H, J=7.2 Hz) ppm; 13C NMR (75 MHz, CDCl3) 172.4, 158.0, 137.8, 131.4, 127.6, 113.8, 60.1, 55.1, 43.2, 35.7, 21.9, 14.1 ppm.

Provenance & Evidence