反应详情

温度

0 °C

To a solution of (R)-2-hydroxy-3-methylbutanoic acid (5.0 gm, 42.2 mmol) in methanol was added a solution of TMS.CH2N2 (2M) in hexane (65 mL), at 0° C., over 20 min. The reaction mixture was stirred at 0° C. for 1 h. The reaction was concentrated with a bath temperature of 20° C. and vacuum greater than 50 mm Hg. Purification via silica gel chromatography using 2-100% EtOAc in hexanes gave the ester as a yellow oil (438 mg, 12.7 mmol, 30% yield). 1H NMR (400 MHz, DMSO-d6) δ 5.30 (d, J=5.1 Hz, 1H), 3.81 (t, J=0.8 Hz, 1H), 3.63 (s, 3H), 1.94-1.86 (m, 1H), 0.88-0.82 (m, 6H).

1. concentrationThe reaction was concentrated with a bath temperature of 20° C. and vacuum greater than 50 mm Hg
2. customPurification via silica gel chromatography