反应详情

温度

0 °C

Methyl chloroformate (58 mL, 750 mmol) was added dropwise to a solution of 2,4-di-tert-butyl-phenol (103.2 g, 500 mmol), Et3N (139 mL, 1000 mmol) and DMAP (3.05 g, 25 mmol) in dichloromethane (400 mL) cooled in an ice-water bath to 0° C. The mixture was allowed to warm to room temperature while stirring overnight, then filtered through silica gel (approx. 1 L) using 10% ethyl acetate-hexanes (˜4 L) as the eluent. The combined filtrates were concentrated to yield carbonic acid 2,4-di-tert-butyl-phenyl ester methyl ester as a yellow oil (132 g, quant.). 1H NMR (400 MHz, DMSO-d6) δ 7.35 (d, J=2.4 Hz, 1H), 7.29 (dd, J=8.5, 2.4 Hz, 1H), 7.06 (d, J=8.4 Hz, 1H), 3.85 (s, 3H), 1.30 (s, 9H), 1.29 (s, 9H).

1. temperatureto warm to room temperature
2. filtrationfiltered through silica gel (approx. 1 L)
3. concentrationThe combined filtrates were concentrated