反应详情

温度

0 °C

Ethyl isobutyrimidate hydrochloride (1.8 g, 11.9 mmol) was suspended in hexanes (29.7 mL) and cooled to 0° C. 2,4,6-Collidine (4.1 mL, 30.9 mmol) and ethyl chloroformate (1.9 g, 17.8 mmol) were sequentially added and the mixture was allowed to warm to RT and stirred for 12 h. Organic solvent was removed in vacuo. The residue was suspended in EtOAc (50 mL) and solids were removed by filtration through a pad of diatomaceous earth. The filter cake was washed with EtOAc (3×10 mL) and the combined filtrates were concentrated in vacuo to afford ethyl N-ethoxycarbonylisobutyrimidate (2.2 g, 99%) as a yellow amorphous solid. 1H NMR (400 MHz, DMSO-d6): δ 4.09 (q, J=7.1 Hz, 2H), 4.03 (q, J=7.1 Hz, 2H), 2.65-2.64 (m, 1H), 1.20 (t, J=7.1 Hz, 3H), 1.19 (t, J=7.1 Hz, 3H), 1.07 (d, J=6.8 Hz, 6H).

1. temperatureto warm to RT
2. customOrganic solvent was removed in vacuo
3. customsolids were removed by filtration through a pad of diatomaceous earth
4. washThe filter cake was washed with EtOAc (3×10 mL)
5. concentrationthe combined filtrates were concentrated in vacuo