反应详情

(R)-2-propyloctanoic acid (0.05 g, 0.268 mmol) was dissolved in 5 mL, CH2Cl2. Triethylamine (50 μL, 0.359 mmol) and 2-bromoacetophenone (0.06 g, 0.300) were added, and the reaction was stirred at room temperature for 5 hours. Once no SM was seen by TLC, the reaction mixture was concentrated under reduced pressure to remove all triethylamine. The residue was purified by silica-gel chromatography (0-10% EtOAc:hexanes) to give the product (Example 2). Ee of >98.5% was determined by HPLC [Chiralcel OJ-RH 4.6×150 mm; CH3CN/H2O=60/40; flow rate 1 mL min−1; detection, 244 nm; retention time, 10.7 min (S) and 11.9 min (R).] 1H-NMR (CDCl3, 500 MHz) δ 7.91 (d, 2H), 7.61-7.57 (m, 1H), 7.48 (t, 2H), 5.32 (s, 2H), 2.55-2.50 (m, 1H), 1.72-1.68 (m, 2H), 1.52-1.48 (m, 2H), 1.47-1.27 (m, 10H), 0.93 (t, 3H), 0.88 (t, 3H).

1. concentrationthe reaction mixture was concentrated under reduced pressure
2. customto remove all triethylamine
3. customThe residue was purified by silica-gel chromatography (0-10% EtOAc:hexanes)
4. customto give the product (Example 2)