反应详情

To a solution of 2,4-dichloro-5-trifluoromethylpyrimidine (2.1 g, 9.77 mmol) in a 1:1 mixture of DCE and t-butanol (20 mL) was added ZnCl2 (1M, 10 mL) and stirred for half an hour at RT. After cooling at 0° C. diethyl 4-amino-2-chloro-3-methoxybenzylphosphonate (3 g, 9.77 mmol) in a 1:1 mixture of DCE and t-butanol (20 mL) was added followed by N-methylimidazole (800 mg, 9.75 mmol) drop wise while stirring was continued for 24 hrs. The solvents were removed under reduced pressure and the residue was purified by column chromatography (SiO2, ethyl acetate and hexanes (1:1)) to yield the desired compound in 1.5 g (32%) yield. 1H NMR (300 MHz, CDCl3) δ 8.61 (s, 1H), 8.38 (d, 1H), 8.03 (s, 1H), 4.01-4.18 (q, 4H), 3.98 (s, 3H), 3.29 (d, 2H), 1.24 (t, 6H).

1. additionwas added
2. stirringwhile stirring
3. customThe solvents were removed under reduced pressure
4. customthe residue was purified by column chromatography (SiO2, ethyl acetate and hexanes (1:1))