反应详情

A solution of trifluoromethanesulfonic anhydride (12.7 g, 45.2 mmol) in 40 mL CH2Cl2 was cooled in an ice bath. A solution of 2-(S)-hydroxy-2-(cyclohexyl)acetic acid, benzyl ester (10.7 g, 43 mmol, from Step A) and 2,6-lutidine (4.6 g, 43 mmol) in 40 mL CH2Cl2 was added dropwise over 25 min and the mixture was stirred for an additional 20 min. The mixture was washed with water and sat'd NaCl then the organic layer was dried over sodium sulfate and concentrated. Flash chromatography (150 g silica, 0→15% EtOAc/hexanes) gave the desired product. 1H NMR (500 MHz, CDCl3) δ1.09-1.33 (m, 5H), 1.66-1.73 (m, 2H), 1.75-1.83 (m, 2H), 2.01-2.08 (m, 1H), 4.98 (d, 1H), 5.27 (d, 1H), 5.29 (d, 1H), 7.35-7.4 (m, 5H).

1. washThe mixture was washed with water
2. dry with materialthe organic layer was dried over sodium sulfate
3. concentrationconcentrated