反应详情

Benzyl alcohol (4.05 mL, 39.1 mmol) was added slowly to a stirring solution of 4-fluorobenzoic acid (5.00 g, 35.7 mmol), 4-(dimethylamino)pyridine (432 mg, 3.53 mmol), and 1,3-dicyclohexylcarbodiimide (8.15 g, 39.5 mmol) in anhydrous CH2Cl2 at room temperature under an argon atmosphere. After 18 h the reaction was worked up according to procedures as outlined for the synthesis of 16. Flash chromatographic purification over silica (10% EtOAc in hexanes) afforded 17 as a clear, colorless liquid (7.75 g, 94%). 1H-NMR (500 MHz, CDCl3) δ 5.35 (s, 2H), 7.06-14 (m, 2H), 7.32-7.41 (m, 3H), 7.41-7.47 (m, 2H), 8.06-8.12 (m, 2H); 13C-NMR (125 MHz, CDCl3) δ 66.84, 115.5 (d, JC-F=22.0 Hz), 126.4 (d, JC-F=2.9 Hz), 128.2, 128.3, 128.6, 132.3 (d, JC-F=9.6 Hz), 135.9, 165.5, 165.8 (d, JC-F=253 Hz); GC-MS 230 m/z [M]+, C14H11OF2 requires 230.

1. customFlash chromatographic purification over silica (10% EtOAc in hexanes)